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Flavonol Glycosides From Consolida Armeniaca, Mustafa Küçüki̇slamoğlu, Nuretti̇n Yayli, Hasan Basri̇ Şentürk, Hasan Genç, Seçki̇n Özden Jan 2000

Flavonol Glycosides From Consolida Armeniaca, Mustafa Küçüki̇slamoğlu, Nuretti̇n Yayli, Hasan Basri̇ Şentürk, Hasan Genç, Seçki̇n Özden

Turkish Journal of Chemistry

Three known flavonol glycosides, i.e., kaempferol 3,7-O-\( \alpha \)-L-dirhamnopyranoside ({\bfseries 1}), kaempferol 3-O-\( \beta \)-D-glucopyranosyl-(1\( \ra \)2)-\( \alpha$-L-rhamnopyranoside-7-O-\( \alpha \)-L-rhamnopyranoside ({\bfseries 2}) and kaempferol 3-O-\( \alpha \)-L-rhamnopyranoside-7-O-\( \beta \)-D-glucopyranosyl-(1\( \ra \)2)-\( \alpha \)-L-rhamnopyranoside ({\bfseries 3}), were isolated for the first time from the flowers of {\itshape Consolida armeniaca}, and the structures of flavonol glycosides were deduced by high field 1D and 2D NMR and FAB-MS spectroscopies. The acetyl derivatives of {\bfseries 1-3} were also prepared ({\bfseries 1a, 2a, 3a}) and identified by NMR and positive FAB mass spectra.


High Fluorescence Emissions Of Some Natural Benzofurane Derivatives Isolated From Styrax Officinalis, Siddik İçli̇, Hüseyi̇n Anil, Bi̇rcan Di̇ndar, Özgen Alankuş Çalişkan, Yurdanur Yayla, Andrey O. Doroshenko, Serap Alp Jan 2000

High Fluorescence Emissions Of Some Natural Benzofurane Derivatives Isolated From Styrax Officinalis, Siddik İçli̇, Hüseyi̇n Anil, Bi̇rcan Di̇ndar, Özgen Alankuş Çalişkan, Yurdanur Yayla, Andrey O. Doroshenko, Serap Alp

Turkish Journal of Chemistry

The fluorescent properties of several natural benzofuran derivatives, egonols, isolated from {\it Styrax officinalis}, were determined. The studied egonol derivatives were found to be effective UV organic luminophores, with quantum yields of near to unity, \( \varphi_{f} \) = 0.92. The fluorescence quenching experiments with electron donor molecules of aniline, N,N-dimethylaniline and carbazolocarbazole, presented very high efficiency of quenching at above diffusion quenching rates of 4.5$\times$10\( ^{10} \), 2.1$\times$10\( ^\times \) and 5.6$\times$10\( ^{12} \) s\( ^{-1} \)mol\( ^{-1} \), respectively. A strong electron acceptor molecule, tetranitrofluorenone, presented quenching rate of 2.6$\times$10\( ^{11} \) s\( ^{-1} \)mol\( ^{-1} \). It …


Heavy Metal Removal From Aquatic Systems By Northern Anatolian Smectites, Çi̇ğdem Arpa, Ridvan Say, Nuray Şatiroğlu, Sema Bektaş, Yuda Yürüm, Ömer Genç Jan 2000

Heavy Metal Removal From Aquatic Systems By Northern Anatolian Smectites, Çi̇ğdem Arpa, Ridvan Say, Nuray Şatiroğlu, Sema Bektaş, Yuda Yürüm, Ömer Genç

Turkish Journal of Chemistry

Competitive adsorption of the heavy metal ions Cu(II), Cd(II) and Pb(II) from aqueous media onto northern Anatolian smectites with a mean particle diameter of 200 $\mu$m, was investigated. The adsorption rate and capacity of the smectite for the selected heavy metal ions, containing different amounts of these ions (5-900 mg/L) at values ranging from pH 1.0 to 7.0 were studied. Very high adsorptions rates were observed at the beginning, and adsorption equilibria were then gradually achieved in about 30 minutes. The maximum adsorption of metal ions onto the smectite were found to be 41.46 mg Cd(II), 36.11 mg Pb(II) and …


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


The Effect Of Peripheral Circuits On The Total \Pi-Electron Energies Of Cyclacenes, Lemi̇ Türker Jan 2000

The Effect Of Peripheral Circuits On The Total \Pi-Electron Energies Of Cyclacenes, Lemi̇ Türker

Turkish Journal of Chemistry

Within the framework of the Hückel molecular orbital theory, certain linear models are developed to express the contribution of peripheral circuits of cyclacenes into their total \pi-electron energies, which explain why cyclacenes exhibit the cryptoannulenic behavior as their peripheral circuits which are annulenic in character.


Spectroscopic Studies Of Charge-Transfer Complexes Of 2,3-Dichloro-5,6-Dicyano-P-Benzo-Quinone, M. S. Subhani̇, N. K. Bhatti̇, M. Mohammad, A. Y. Khan Jan 2000

Spectroscopic Studies Of Charge-Transfer Complexes Of 2,3-Dichloro-5,6-Dicyano-P-Benzo-Quinone, M. S. Subhani̇, N. K. Bhatti̇, M. Mohammad, A. Y. Khan

Turkish Journal of Chemistry

Charge-transfer complexes of 2,3-dichloro-5, 6-dicyano-p-benzoquinone (DDQ) p-acetotoluidide, acetanilid, biphenyl and naphthalene were studied and their absorption spectra in solution were recorded. Absorption spectral data were obtained in CH_2Cl_2, CHCl_3, CCl_4 and mixture (CH_2Cl_2 + V) at different temperatures. Two charge-transfer bands were observed in each case. Spectral characterization of these complexes was determined and correlated with the ionization potential of the donor. Variation in thermodynamic parameters were also found to be due to change in donor and solvent.


Atmospheric Deposition Of Pb, Zn, Cu, And Cd In Amman, Jordan, Kamal A. Momani, Anwar G. Jiries, Qasem M. Jaradat Jan 2000

Atmospheric Deposition Of Pb, Zn, Cu, And Cd In Amman, Jordan, Kamal A. Momani, Anwar G. Jiries, Qasem M. Jaradat

Turkish Journal of Chemistry

Atmospheric samples were collected using a low-volume air sampler and dustfall containers during the summer of 1995 at different sites in the city of Amman, Jordan. The heavy metal contents in settleable particles (dustfall) as well as in air particulates (suspended) were analyzed by graphite furnace atomic absorbation spectrophotometry. The atmospheric concentrations of Zn, Cu, Pb, and Cd were 344, 170, 291, and 3.8 ng/m$^3$, respectively. The levels of these elements in the dustfall deposition were 505, 94, 74 and 3.1 $\mu$g/g, respectively. The fluxes and dry deposition velocities of these heavy metals were determined and compared with the findings …


Impedance Measurements Of Polyester-Coated Galvanised Mild Steel In 10xacid Rainwater After An Accelerated Wet-Dry Test, İlyas Dehri̇ Jan 2000

Impedance Measurements Of Polyester-Coated Galvanised Mild Steel In 10xacid Rainwater After An Accelerated Wet-Dry Test, İlyas Dehri̇

Turkish Journal of Chemistry

The variation of defective polyester-coated performance with time in 10xacid rain solution was investigated using electrochemical impedance spectroscopy. Measurements were carried out on samples after an accelerated atmospheric corrosion test. The impedance diagrams (Nyquist plots) were simulated using the EQUIVCRT program which was elaborated by Boukamp and the semi-ellipse model which was developed by Erbil. It has been shown that the defective coating resistance changes with time for the samples subjected to acid rainwater. The corrosion rate of coated metal also changes with time.


Kinetics And Thermodynamics Of Oil Extraction From Sun Ower Seeds In The Presence Of Aqueous Acidic, Hüseyi̇n Topallar, Ümi̇t Geçgel Jan 2000

Kinetics And Thermodynamics Of Oil Extraction From Sun Ower Seeds In The Presence Of Aqueous Acidic, Hüseyi̇n Topallar, Ümi̇t Geçgel

Turkish Journal of Chemistry

Oil extraction was performed in aqueous HCl, H_2SO_4 and H_3PO_4 solutions with n-hexane (C_6H_{14}) at 30, 40, 50 and 60 ^oC using 10 gr of sunflower seeds over 1 h with 10-min. sampling intervals. The optimum acid concentration was wt. 10% for each acid, and the highest oil yield was obtained in the extraction procedure with n-hexane containing H_2SO_4. The extraction process was observed with regard to the percent oil yield versus time, and the reaction order was found to be first-order kinetics by the differential method. The activation energy for the oil extraction kinetics of sunflower seeds with 10% …


Synthesis Of A New Dihydropyridine Derivative Containing A Known Vasodilator Khellin, Gülgün Ayhan Kilcigi̇l, Meral Tunçbi̇lek, Rahmi̇ye Ertan, Kevser Erol, Engi̇n Yildirim Jan 2000

Synthesis Of A New Dihydropyridine Derivative Containing A Known Vasodilator Khellin, Gülgün Ayhan Kilcigi̇l, Meral Tunçbi̇lek, Rahmi̇ye Ertan, Kevser Erol, Engi̇n Yildirim

Turkish Journal of Chemistry

The synthesis and spasmolytic activity of a novel dihydropyridine derivative which contains a vasodilator furanochromone khellin at the 4^{th}$ position of the dihydropyridine ring via the Hantzsch method from khellin-2-carboxaldehyde is described.


The Effect Of Acetone On Calomel Formation On A Mercury Film Electrode Surface In Chloride Medium, F. Ni̇l Ertaş, H. İsmet Gökçel, Hüseyi̇n Tural Jan 2000

The Effect Of Acetone On Calomel Formation On A Mercury Film Electrode Surface In Chloride Medium, F. Ni̇l Ertaş, H. İsmet Gökçel, Hüseyi̇n Tural

Turkish Journal of Chemistry

In the presence of chloride ions, calomel formation takes place on the mercury thin film electrodes under open-circuit conditions, which leads to high base currents and erratic performance in ASV meas- urements. This study describes the effect of chloride concentration on the calomel formation on the surface by following the cathodic peak on the anodic scan. The effect of acetone on the surface reaction and baseline stability was studied. Application of the method with a sea water sample is also given.


The Rate Of Grafting And Some Kinetic Parameters Of The Graft Copolymerization Of Methacrylic Acid On Poly (Ethylene Terephthalate) Fibers With Azobisisobutyronitrile, Meltem Çeli̇k, Mehmet Saçak Jan 2000

The Rate Of Grafting And Some Kinetic Parameters Of The Graft Copolymerization Of Methacrylic Acid On Poly (Ethylene Terephthalate) Fibers With Azobisisobutyronitrile, Meltem Çeli̇k, Mehmet Saçak

Turkish Journal of Chemistry

In this study the rate of grafting and some kinetic parameters of the graft copolymerization of methacrylic acid on poly(ethylene terephthalate) fibers with azobisisobutyronitrile was investigated. The rate of grafting was found to be proportional to the 0.94 and 1.22 powers of initiator and monomer concentrations, respectively. By carrying out the graft copolymerization reaction at four different temperatures ranging from 70 ^oC to 90 ^oC, the overall rate activation energy of the reaction was found to be 130.4 kJ/mol. The overall rate constants were also calculated.


Modification Of Polyester And Polyamide Fabrics By Different In Situ Plasma Polymerization Methods, T. Öktem, N. Seventeki̇n, H. Ayhan, Erhan Pi̇şki̇n Jan 2000

Modification Of Polyester And Polyamide Fabrics By Different In Situ Plasma Polymerization Methods, T. Öktem, N. Seventeki̇n, H. Ayhan, Erhan Pi̇şki̇n

Turkish Journal of Chemistry

In order to increase the hydrophilicities, and therefore to impart soil resistance and to improve dyeability, poly(ethylene terephthalate) (PET) and polyamide (PAm) fabrics were treated in low-temperature plasmas. Five different modification types were applied. Fabrics were directly treated in acrylic acid, water, air, O_2 and argon plasma. The plasma conditions (i.e., exposure time and discharge power) were changed to control the extent of plasma surface modification. Wettability, soil resistance and dyebility of PET fabrics were significantly improved by this method. More hydrophilic surfaces were created by all the methods.


Spectrophotometric Determination Of Selenium (Iv) Using Methdilazine Hydrochloride, Mahaveer B. Melwanki, Jaldappa Seetharamappa Jan 2000

Spectrophotometric Determination Of Selenium (Iv) Using Methdilazine Hydrochloride, Mahaveer B. Melwanki, Jaldappa Seetharamappa

Turkish Journal of Chemistry

Methdilazine hydrochloride is proposed as a selective and sensitive reagent for the spectrophotometric determination of selenium (IV). The reagent forms a red radical cation by selenimum (IV) in hydrochloric acid medium and exhibits an absorption maximum at 513 nm. Beer's law is valid over the concentration range 0.1-2.3 mg1^{-1} of selenium (IV). Sandell's sensitivity of the reaction is found to be 3.57 ng cm^{-2} and the molar extinction coefficient is 9.32 x 10^4 1 mol^{-1} cm^{-1} at 513 nm. The effects of acidity, reagent concentration, temperature and diverse ions upon the absorbance of the red species are critically assessed. The …


Adsorption Of Some Heavy Metal Ions From Aqueous Solution By Activated Carbon And Comparison Of Percent Adsorption Results Of Activated Carbon With Those Of Some Other Adsorbents, İlhan Uzun, Fuat Güzel Jan 2000

Adsorption Of Some Heavy Metal Ions From Aqueous Solution By Activated Carbon And Comparison Of Percent Adsorption Results Of Activated Carbon With Those Of Some Other Adsorbents, İlhan Uzun, Fuat Güzel

Turkish Journal of Chemistry

In this study, removal of some heavy metals ions (Mn^{2+}, Fe^{2+}, Ni^{2+} and Cu^{2+}) from aqueous solution by adsorption was investigated. For this purpose, high-grade MnSO_4.H_2O, FeSO_4.7H_2O, NiSO_4.7H_2O and CuSO_4.5H_2O were used as heavy metal samples. The commercial activated carbon (Merck 2514), chitosan and agar were used as adsorbents. The pH of each solution was not controlled. This is because the net interaction between the adsorbent and the heavy metal could be disturbed by the buffer solution. Therefore, all experiments were carried out in a pH range from 5.3 to 5.5. The equilibrium adsorption contact times were determined for M …


Polarographic Determination Of Fluvoxamine Maleate In Tablets, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Sidika Sungur, Şule Aycan Jan 2000

Polarographic Determination Of Fluvoxamine Maleate In Tablets, Fi̇kri̇ye Elmali, Güzi̇n Alpdoğan, Sidika Sungur, Şule Aycan

Turkish Journal of Chemistry

The differential pulse polarographic (DPP) method was developed for the determination of fluvoxamine maleate (I). At pH = 3. 7, (I) give a peak at - 0. 73 V in aqueous solution. The developed method was applied to the assay of the drug substance in commercial tablet formulations. The results were statistically compared with those obtained by reference methods (HPLC and direct current polarographic method) using t- and F- tests at 95 % confidence level.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Electrothermal Atomic Absorption Spectrometric Determination Of Nickel After Its Flotation Enrichment By Iron(Iii) Hexamethylenedithiocarbamate, Trajce Stafilov, Gorica Pavlovska, Katarina Cundeva Jan 2000

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 …


Electroreduction Of Some Diazine And Triazine Pesticides At The Dropping Mercury Electrode, Petr Zuman, Marina Privman, Masami Shibata, Jiri Ludvik Jan 2000

Electroreduction Of Some Diazine And Triazine Pesticides At The Dropping Mercury Electrode, Petr Zuman, Marina Privman, Masami Shibata, Jiri Ludvik

Turkish Journal of Chemistry

Electroanalytical methods enable determination of electroactive species in nonhomogeneous systems, as limiting currents are little affected by the presence of solid and colloidal particles. An example of such applications of electrochemical methods are studies of binding of toxic substances, such as pesticides, on slightly soluble polymers, such as lignin. To successfully apply polarographic methods for following free pesticides in a slurry of lignin, it is first necessary in principle to elucidate the electrochemical processes involved. In aqueous buffered solutions the electron transfers, in which organic compounds participate, are in the majority of cases accompanied by chemical reactions. To elucidate the …


Synthetic Metal Alloys: Preparation Of Polyaniline/Polypyrrole Alloys In Protic Medium, Fati̇h Köleli̇, Meltem Düdükcü, Yasemi̇n Arslan Jan 2000

Synthetic Metal Alloys: Preparation Of Polyaniline/Polypyrrole Alloys In Protic Medium, Fati̇h Köleli̇, Meltem Düdükcü, Yasemi̇n Arslan

Turkish Journal of Chemistry

Pyrrole and aniline solutions were mixed in different ratios and oxidized under anodic conditions on Pt surface in protic medium. The electrocopolymerization and electrochemical properties of these alloys were investigated. Current-potential diagrams of polyaniline (PA), polypyrrole (PP) and the resulting alloys were recorded and their electrochemical characterizations were identified. In-situ resistance measurements of synthesized alloys were carried out with a home-made apparatus. Conductivity of alloys showed changes depending on applied potential as intrinsic polymers. The electrochemical behaviour of homopolymers and alloys was studied at different temperatures.


A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler Jan 2000

A Convenient Synthesis Of Some 4-(Alkylamino)-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones, Bahi̇tti̇n Kahveci̇, Aykut İki̇zler

Turkish Journal of Chemistry

A series of 3-alkyl-4-(arylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 6-10,} was obtained from the reaction of the corresponding 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones, {\bfseries 1,} with the appropriate aldehydes. 3-alkyl-4-(alkylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones of type {\bfseries 11-16} were synthesized from the selective reduction of compounds {\bfseries 5-10} with NaBH$_{4}$ in diglyme or DMSO medium as a general and convenient method.


Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz Jan 2000

Ion-Selective Membrane Electrode For The Determination Of A Novel Phenylpiperazine Antidepressant, Nefazodone, Arzum Erdem, Di̇lşat Özkan, Kağan Kerman, Burcu Meri̇ç, Tayfun Dalbasti, Mehmet Özsöz

Turkish Journal of Chemistry

The construction and performance characteristics of ion-selective membrane electrodes for a newly found phenylpiperazine antidepressant, Nefazodone (NFN), based on its ion-pair complexes with phosphotungstate (PT), tetraphenylborate (TPB), tungstosilicate (TS) and reineckate (RN) in a poly(vinyl chloride) (PVC) matrix are described. The best ion-selective electrode for determination of NFN contains NFN-PT as the active material. This electrode exhibits a Nernstian response (62.6 ± 0.4 mV per decade) in the range 1.5 x 10$^{-5}$ to 1.0 x 10^{-2} M NFN.HCl in solutions. The selectivity of this electrode to NFN in the presence of a number of sugar molecules, cations and drugs is …


Investigation Of The Synthesis Of Some Dehydroalanine Derivatives, Si̇bel Süzen, John Michael Williams Jan 2000

Investigation Of The Synthesis Of Some Dehydroalanine Derivatives, Si̇bel Süzen, John Michael Williams

Turkish Journal of Chemistry

Dehydroamino acids represent an important class of compound as they are key intermediates in unusual amino acid and in the design of peptides and are constituents of a variety of naturally occurring antibiotic and phytotoxic peptides. In view of the importance of proteins and peptides containing hydroxyamino acids and the problems associated with their synthesis and dehydration, an investigation was performed on model compounds in order to examine the difficulties of the dehydration reactions. The preparation and properties of the model dehydroalanine derivatives have been studied.


Hplc/Hydride Generation Aas Coupling For The Speciation Of Sb(Iii) And Sb(V) In Wastewaters, Nuray Şatiroğlu, Sema Bektaş, Ömer Genç, Haydar Hazel Jan 2000

Hplc/Hydride Generation Aas Coupling For The Speciation Of Sb(Iii) And Sb(V) In Wastewaters, Nuray Şatiroğlu, Sema Bektaş, Ömer Genç, Haydar Hazel

Turkish Journal of Chemistry

A comparative study was made with two HPLC columns of different lengths (PRP-X 100, 250 mm \( \times \) 4.1 mm id and PRP-X 100, 100 mm \( \times \) 4.1 mm id) coupled to HGAAS for the speciation of inorganic Sb(III) and Sb(V) species. The effects of eluent concentration and pH on the retention times of Sb species in both columns were investigated. The separation of Sb species was realized by using 50 mmol/L citrate solution at pH 4.0 as the eluent. The retention times were 2.0 min and 10.0 min in the 250 mm column, and 1.4 min …


Zinc Determination In Pleural Fluid, Nazan Demi̇r, Yaşar Demi̇r, Ebubeki̇r Bakan, İrfan Küfrevi̇oğlu Jan 2000

Zinc Determination In Pleural Fluid, Nazan Demi̇r, Yaşar Demi̇r, Ebubeki̇r Bakan, İrfan Küfrevi̇oğlu

Turkish Journal of Chemistry

In this study, an enzymatic zinc determination method was applied to pleural fluid, the basis of which was the regaining of the activity of apo carbonic anhydrase by the zinc present in the sample. The method was used for pleural fluid zinc determination in order to show the application to body fluids other than serum. For this purpose, pleural fluids were obtained from 20 patients and zinc concentrations were determined. Carbonic anhydrase was purified by affinity chromatography from bovine erythrocytes. The zinc present in its structure was removed by dialysis against dipicolinic acid, resulting in apoenzyme obtained at a ratio …


X-Ray Powder Diffraction And Ir Study Of Calcium Borophosphate Cabpo_5, A. Baykal, G. Gözel, Meral Kizilyalli, M. Toprak, R. Kniep Jan 2000

X-Ray Powder Diffraction And Ir Study Of Calcium Borophosphate Cabpo_5, A. Baykal, G. Gözel, Meral Kizilyalli, M. Toprak, R. Kniep

Turkish Journal of Chemistry

In this study, CaBPO_5 was synthesized by different solid state reactions than reported before and its X-ray powder diffraction and IR data were reported. In one of these solid state reactions BPO_4 was used as a phosphating agent. The examination of the X-ray powder diffraction data showed that this compound crystallized in a hexagonal system and the refined unit cell parameters were a = 6.684, c = 6.616(2) \AA, with Z=3 as reported before. From the observed reflections, the space group was determined as P3_121, and its density was found to be 3.15 g/cc. The X-ray powder diffraction and IR …


All Solid-State Contact Lead(Ii) Ion-Selective Pvc Membrane Electrode Using Dimethylene Bis(4-Methylpiperidinedithiocarbamate) Neutral Ionophore, İbrahi̇m Işildak Jan 2000

All Solid-State Contact Lead(Ii) Ion-Selective Pvc Membrane Electrode Using Dimethylene Bis(4-Methylpiperidinedithiocarbamate) Neutral Ionophore, İbrahi̇m Işildak

Turkish Journal of Chemistry

All solid-state contact PVC membrane electrodes for lead(II) ion were developed by using dimethylene bis(4-methylpiperidinedithiocarbamate) as neutral carrier and nitrophenyloctyl ether or dioctylsebacate as plasticizers. Response properties of the all solid-state contact PVC membrane electrode prepared with nitrophenyloctyl ether were better than those of the membrane electrode prepared with dioctylsebacate. The nitrophenyloctyl ether plasticized the all solid-state contact PVC membrane electrode and exhibited a good linear response of 30 mV/decade for lead(II) ion within the concentration ranges \( 0.1-5\times10^{-6} \) mol dm\( ^{-3} \) lead(II) nitrate, good selectivity over alkali, alkali-earth and transition metal ions including copper(II) ion by a …


High-Performance Liquid Chromatographic Determination Of Oxytetracycline Residue In Cured Meat Products, Hami̇de Z. Şenyuva, Tuncel Özden, Deni̇z Yurtsever Sarica Jan 2000

High-Performance Liquid Chromatographic Determination Of Oxytetracycline Residue In Cured Meat Products, Hami̇de Z. Şenyuva, Tuncel Özden, Deni̇z Yurtsever Sarica

Turkish Journal of Chemistry

The development of a sensitive automated method for residue control of oxytetracycline (OTC) in cured meat (soudjouk) is described. The principle steps involve the extraction of OTC from cured meat in the presence of citric acid with nitric acid, methanol and de-ionized water, and then the determination by HPLC. In HPLC, Hypersil BDC C18 column was used and OTC was separated at 24 ^{o}C using a mobile phase of H_2O (pH=2.10 with H_2SO_4): ACN (85:15, v/v) at a flow rate of 1.5 ml/min. A variable wavelength detector was set at 360 nm. The detection limit of the method was calculated …


Investigation Of The Influence Of Thiocarbamide In The Process Of Carbamide Deparaffinization, Sevi̇l Veli̇yeva Jan 2000

Investigation Of The Influence Of Thiocarbamide In The Process Of Carbamide Deparaffinization, Sevi̇l Veli̇yeva

Turkish Journal of Chemistry

The influence of thiocarbamide in the process of carbamide dewaxing was investigated. The dependence of separated paraffins on the quantity of thiocarbamide was examined experimentally. It was determined that the separation of paraffins becomes equal to zero when moles of carbamide and thiocarbamide in water-isopropyl alcohol solution are equal. The low-temperature qualities (the temperature of dimness and freezing) of dewaxed fuels were also examined. By using infrared spectroscopy methods, the compound of received paraffins was investigated.


Cover And Contents Jan 2000

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.