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The Mechanism Of The Photoprotolytic Reactions Of Some Oxyazomethine Compounds, Lubov Efimovna Zelt'ser, Milan B. Bastic, Ljubinka V. Rajakovic
The Mechanism Of The Photoprotolytic Reactions Of Some Oxyazomethine Compounds, Lubov Efimovna Zelt'ser, Milan B. Bastic, Ljubinka V. Rajakovic
Turkish Journal of Chemistry
The kinetic spectral study of the photoprotolytic reactions of oxyazomethine molecules was performed. It was established that the deprotonation reactions of oxyazomethines proceed with the participation of electronically excited molecules and are characterized by parameters which differ to basic state reactions.
Distribution Of Ce (Iv) Species In Hno_{3}-Hcio_{4} Media And Determination Of Stability Constants Of The Nitrato Complexes, Seval Bayülken, A. Sezai Saraç
Distribution Of Ce (Iv) Species In Hno_{3}-Hcio_{4} Media And Determination Of Stability Constants Of The Nitrato Complexes, Seval Bayülken, A. Sezai Saraç
Turkish Journal of Chemistry
In this paper, the distribution of cerium (IV) species depending on the charges of nitric acid-perchloric acid concentration at constant ionic strength (I=1.0) was investigated. Cerium (IV), being a strong oxidant, was utilized for investigating the oxidation kinetics of some amino acids. Knowing the distribution of cerium (IV) species is beneficial for better understanding this type of kinetics. Distribution of cerium (IV) species in aqueous media was studied by measuring the total optical absorbance of cerium (IV) species in different nitric acid-perchloric acid mixture solutions. The stability constants (K_{1} and K_{2}) of the nitrato cerium complexes were determined spectrophotometrically from …
Automation Of Dipole Moment Measurements Using Microprocessor Controlled System, Nil Tarim, Hakan Kuntman, Ayten Kuntman
Automation Of Dipole Moment Measurements Using Microprocessor Controlled System, Nil Tarim, Hakan Kuntman, Ayten Kuntman
Turkish Journal of Chemistry
A microprocessor controlled instrument that can be used in physical chemistry research laboratories has been designed and constructed. The intended use is the measurement of the dipole moment and determination of the temperature dependency of the dipole moment for polar substances, especially for macromolecules. Measurement techniques with conventional dipolmeters require fine adjustments and measurements which seem to be very tedious and time consuming. Provided automation enables very frequent measurements with a step of 1^{\circ}C and disallows any user-oriented error. The dielectric constant measurement is performed within an accuracy limit of less than \pm 0.001. Furthermore, the equipment designed provides the …
Polyelectrolytes In Immunology: Fundametals And Perspectives, Mehmet I. Mustafaev
Polyelectrolytes In Immunology: Fundametals And Perspectives, Mehmet I. Mustafaev
Turkish Journal of Chemistry
Physico-chemical criteria for the construction of artifical immunomodulators and immunogens(and vaccines) on the basis of synthetic polyelectrolyte(PE) and polyelectrolyte complexes(PEC) with low molecular weight ligands and protein (and polysaccharide) antigens are considered. The role of electric charge, chain length, conformation, hydrophobicity, polydispersity and supramolecular structure in the immunomodulating activity of PE(PEC) and the conditions facilitating the transformation of their suppressor capacity into immunostimulating one in the same polymerhomologues series are discussed. A structure-function relationship of immunogenicity of PE(PEC), a structural model of an artificial polymer- subunit immunogen and some practical applications of them as valuable tools in theoretical immunological studies …
Enantioselective Synthesis Of 4-Hydroxy-3-(3-Oxo-1-Phenyl Butyl)- 2h-1-Benzopyran-2-One (Warfarin), Ayhan S. Demi̇r, Cihangir Tanyeli, Volkan Gülbeyaz, Hülya Akgün
Enantioselective Synthesis Of 4-Hydroxy-3-(3-Oxo-1-Phenyl Butyl)- 2h-1-Benzopyran-2-One (Warfarin), Ayhan S. Demi̇r, Cihangir Tanyeli, Volkan Gülbeyaz, Hülya Akgün
Turkish Journal of Chemistry
Oral anticoagulant Warfarin (4-hydroxy-3-(3-oxo-1-phenyl butyl)-2H-1- benzopyran-2-one) is synthesized in optically active form starting from 4- hydroxycoumarin via formation of optically active enamines followed by Michael addition reaction with benzyliden acetone at low temperature. Different amines gave 17-68\% ee and the chemical yield was 22-71\%, depending on the reaction conditions and the structure of chiral amines.
The Determination Of Some Heavy Metal Cations By Tlc/Photodensitometry, Şahin Savaşçi, Mehmet Akçay
The Determination Of Some Heavy Metal Cations By Tlc/Photodensitometry, Şahin Savaşçi, Mehmet Akçay
Turkish Journal of Chemistry
The samples having complex matrices were analyzed for some heavy metal cations by using a thin layer chromatography/photodensitometry (TLC/PD) system. The rock samples were dissolved by suitable methods. Nickel, Cobalt and Copper were dedected and analyzed by photodensitometric comparison of corresponding spots of samples with those of standards. The results of the same samples and standards were compared with those obtained by atomic absorption measurements. Our results are comparable with the results of flame atomic absorption measurements. The precision of TLC method was calculated to be 9.4\% as relative standard deviations depending on 17 replicate measurements. The accuracy of TLC …
Molecular Structure Of 2'-Hydroxy-3'-Methoxy-5'-Allyl -4-Methylazobenzene, Veysel T. Yilmaz, Selami Şasmaz, İsmail E. Gümrükçüoğlu, R. Alan Howie
Molecular Structure Of 2'-Hydroxy-3'-Methoxy-5'-Allyl -4-Methylazobenzene, Veysel T. Yilmaz, Selami Şasmaz, İsmail E. Gümrükçüoğlu, R. Alan Howie
Turkish Journal of Chemistry
2'-hydroxy-3'-methoxy-5'-allyl-4-methylazobenzene was synthesized in two steps: 4-methylbenzenediazonium chloride was prepared by the reaction of 4- methylaniline, HCL and NaNO_{2}, and was then reacted with eugenol to give 2'-hydroxy-3'-methoxy-5'-allyl-4-methylazobenzene. The molecular structure was identified by UV/VIS, IR, ^{1}H-NMR and elemental analysis. The crystal structure was determined as monoclinic by single crystal X-ray diffraction technique. The final R values was found to be 0. 078 for 1065 observed reflections. The structure consists of isolated molecules with van der Waals contacts and the molecule is essentially planar in the solid state. There is a strong intramolecular hydrogen bond in which the hydroxyl group …
Synthesis Of Some Pyrazolo-Pyridazine Compounds, Adem Önal, Yunus Akçamur, Behzat Altural
Synthesis Of Some Pyrazolo-Pyridazine Compounds, Adem Önal, Yunus Akçamur, Behzat Altural
Turkish Journal of Chemistry
Addition of {\bf 1} to two moles of phenylhydrazine gives 1,2,4,6- tetraphenyl-(2,3-d)-pyrazolo-5,6-pyridazine-7-one {\bf 4} isomer compound 1, 2,3,5-tetraphenyl-(2,3-d) pyrazolo-5,6-pyridazine-7-one {\bf 5} of {\bf 4} was synthesized by the reaction of {\bf 2} with phenylhydrazine. 3,4- Diphenyl-(2,3-d)-pyrazolo-(1H,6H)-pyridazine-7-one {\bf 6} was also obtained in two different ways. Reaction of {\bf 1} and 4-benzoyl-5 phenyl- furan-2,3-dione {\bf 3} with hydrazinium hydrate furnished compound {\bf 6}. The structures of {\bf 4,5} and {\bf 6} were determined by the ^{13} C- NMR, IR spectra and elemental analysis. These new isomer and condensed compounds synthesized in this study are important for heterocyclic chemistry.
Cycloaddition Reactions Of Dichloroketene To Allyl Ethers, Hülya Şenöz, Süleyman Yildirir
Cycloaddition Reactions Of Dichloroketene To Allyl Ethers, Hülya Şenöz, Süleyman Yildirir
Turkish Journal of Chemistry
Allyl ethers reacted with dichloroketene by [2+2] Cycloaddition to produce 2,2-dichlorocyclobutanones structure of products were determined by IR, NMR, GC MS tecniques.
Fixed Bed Pyrolysis And Hydropyrolysis Of An Immature Type I Turkish Oil Shale, Murat Çitiroğlu, Selma Türkay, Zeynep Işık Cepni̇, Colin Edward Snape
Fixed Bed Pyrolysis And Hydropyrolysis Of An Immature Type I Turkish Oil Shale, Murat Çitiroğlu, Selma Türkay, Zeynep Işık Cepni̇, Colin Edward Snape
Turkish Journal of Chemistry
A number of different pyrolysis procedures were investigated in order to achieve higher oil yields from an immature type I oil shale than obtained under static retorting conditions. Both nitrogen and steam gases increased yields as inticipated: Steam achieving comparable yields to nitrogen but at much lower gas velocities. The composition of the tars varied considerably, steam increasing the concentration of alkenes. In coprocessing the oil shale with a Turkish lignite in the Heinze retort, oil yields were higher than predicted principally due to extraction of the lignite by pyrobitumens obtained from the oil shale. Fixed bed hydropyrolysis of the …
Synthesis Of 2[1'(3',5'-Disubstituted Pyrazolyl) Methyl]5-Phenyl Amino-1,3,4-Thiadiazoles And 1,2,4-Triazoles As Potential Therapeutic Agents, Roshan Ahmad, M. Zia-Ul-Haq, Rukhsana Jabeen, Helmut Duddeck
Synthesis Of 2[1'(3',5'-Disubstituted Pyrazolyl) Methyl]5-Phenyl Amino-1,3,4-Thiadiazoles And 1,2,4-Triazoles As Potential Therapeutic Agents, Roshan Ahmad, M. Zia-Ul-Haq, Rukhsana Jabeen, Helmut Duddeck
Turkish Journal of Chemistry
A complete synthesis of 2[1'(3', 5'-disubstituted pyrazolyl) methyl] 5- phenyl-1,3,4-thiadiazole V(a-b) and 1,2,4-trizole VI (a-b) is reported. Cyclocondensation of \beta-diketones with etylhydrazino acetate hydrochloride yielded ethyl 3,5-disubstituted pyrazolyl acetate II(a-c) which on treatment with hydrazine hydrate resulted in the formation of their hydrazide derivatives III(a-c). These hydrazides, when treated with phenyl isothiocyanate, gave thiosemicarbazide derivatives IV(a-c), which were cyclised in the presence of con. H_{2}SO_{4} and NaOH to give V(a-b) and VI(a-b), respectively.
Extraction Of Dyestuff From Onion (Allium Cepa L.) And Its Application In The Dyeing Of Wool, Feathered-Leather And Cotton, Adem Önal
Turkish Journal of Chemistry
In this study, the total amount of dyeing substances present in onion (Allium cepa L.) was determined by using the extraction method. The extracted substanc were used in the dyeing of woollen strips, feathered- leather and cotton. Dyeing conditions and other characteristics were determined and the repeatable specifics were evaluated for these processes so that ligh fast colours could be obtained.
Extraction Of Dyestuff From Madder Plant ( Rubia Tinctorum L.) And Dyeing Of Wool, Feathered-Leather And Cotton}, Adem Önal
Turkish Journal of Chemistry
In this study, the total amount of dyeing substances present in {\it Rubia tinctorum L}. was found by using the extraction method and then separated in column. All of the dyeings were carried out with red component alizarin (1,2-dihydroxyanthraquinone). Dyeing conditions and other characteristics were determined and in most cases high fast colours were obtained.
Circular Dichroism Studies Of Complexation Of Antibiotic (+)- Cephradine With Cr(Iii), Co(Ii) And Ni(Ii) In Methanol: Water (80:20) Solution, Nasir Ahmad, Javed Safder, Christy Munir
Circular Dichroism Studies Of Complexation Of Antibiotic (+)- Cephradine With Cr(Iii), Co(Ii) And Ni(Ii) In Methanol: Water (80:20) Solution, Nasir Ahmad, Javed Safder, Christy Munir
Turkish Journal of Chemistry
Circular dichroism (CD) studies have been utilized to investigate complexation of antibiotic (+)-cephardine with Cr(III), Co(II) and Ni(II) ions in methanol: water (80:20 v/v) solution. The optimum conditions of pH, stoichiometry and time for achieving equilibrium for maximum complexation in these systems are determined. The CD spectra of these complex ions consist of 2-3 Cotton bands between 16,129-25,994 cm^{-1} with differential absorptivity 0.0046-0.428 deg. L mol^{-1} cm^{-1} and bands are assigned to electronic transitions. The formation constants of these complexes in mixed solvent are reported.
Extractive Spectrophotometry Of Palladium(Ii) With 3,4,5- Trimethoxybenzaldehyde Thiosemicarbazone, A. M. A. Khader, K. S. Prasad
Extractive Spectrophotometry Of Palladium(Ii) With 3,4,5- Trimethoxybenzaldehyde Thiosemicarbazone, A. M. A. Khader, K. S. Prasad
Turkish Journal of Chemistry
The extractive spectrophotometric determination of palladium(II) using 3,4, 5-trimethoxybenzaldehyde thiosemicarbazone (TBTSC) is discussed in this study. It forms an intense yellow-coloured chloroform-soluble complex with paladium(II) in an acidic medium. The molar absorptivity at 370nm is 8.35x 10^{4} 1. mol^{-1} cm^{-1}. The complex system conformed to Beer's Law up to a concentration limit of 12 ppm. The Sandell's sensitivity was 8. 57 ng. cm^{-2}. The interference of various ions was studied, and palladium(II) in its alloy compositions was analysed.
Synthesis Of Optically Active Camphorsulphonylbenzimidazoles, Mashooda Hasan, Humaira Masood, Naeema Khan, M. Zia-Ul-Haq
Synthesis Of Optically Active Camphorsulphonylbenzimidazoles, Mashooda Hasan, Humaira Masood, Naeema Khan, M. Zia-Ul-Haq
Turkish Journal of Chemistry
The preparation of optically active camphorsulphonylbenzimidazole {(\bf 1)}, a mixture of regioisomeric 5-nitro- {\bf (2A)} and 6-nitro-{\bf (2B)} camphorsulphonylbenzimidazoles, 5-nitro-{\bf (3A)} and 6-nitro-{\bf (3B)} 2- methyl camphorsulphonylbenzimidazoles is described. In this study the structure of the purified camphorsulphonylbenzimidazoles {\bf 1, 2B, 3A} and {\bf 3B} was confirmed by their mass and ^{1}H NMR spectral analysis. The specific rotation of each pure compound is also reported.
A Comparison Of Adsorption Isotherms Of Crosslinked Poly(N-Vinylpyrrolidone)/Basic Brown 1 Binding System, Dursun Saraydin, Erdener Karadağ
A Comparison Of Adsorption Isotherms Of Crosslinked Poly(N-Vinylpyrrolidone)/Basic Brown 1 Binding System, Dursun Saraydin, Erdener Karadağ
Turkish Journal of Chemistry
In this study, the binding of a basic dye such as basic brown 1 [BB 1] onto a crosslinked poly(N-vinylpyrrolidone) [CPVP] was investigated. Adsorption of the azo dye onto the CPVP was studied by the batch adsorption technique at 25^{\circ}C. In adsorption experiments a Langmuir type (L) adsorption was found with respect to the Giles classification system. Binding parameters such as initial binding constant (K_{i}), equilibrium constant {\it (K)}, monolayer coverage (n), site-size (u), and maximum fractional occupancy (\hat{\theta}), and thermodynamic parameters such as heat of adsorption (\Delta H), free energy of adsorption (\Delta G) and entropy of adsorption (\Delta …
The Facile Synthesis Of Cyclopentanoid Antibiotic Kjellmanianone, Ayhan S. Demi̇r, Cihangir Tanyeli̇, Volkan Gülbeyaz, Hülya Akgül
The Facile Synthesis Of Cyclopentanoid Antibiotic Kjellmanianone, Ayhan S. Demi̇r, Cihangir Tanyeli̇, Volkan Gülbeyaz, Hülya Akgül
Turkish Journal of Chemistry
The synthesis of cyclopentanoid antibiotic Kjellmanianone is described in this study. The C-acylation of lithium enolates of 3-Methoxycyclopentenone by N-carbomethoxyimidazole or methylcyanoformate \beta-ketoester, which when oxidized with Mn(III) acetate produces kjellmanianone in good yield.
Oxidative Coupling Of Methane On Lnba_{2}Cu_{3}O_{7-X} Superconductors, N. T. Shamilov, V. P. Vislovskii, E. A. Mamedov, S. M. Aliyev, A. I. Suleimanov, E. G. Ismailov
Oxidative Coupling Of Methane On Lnba_{2}Cu_{3}O_{7-X} Superconductors, N. T. Shamilov, V. P. Vislovskii, E. A. Mamedov, S. M. Aliyev, A. I. Suleimanov, E. G. Ismailov
Turkish Journal of Chemistry
The superconducting oxides LnBa_{2}Cu_{3}O_{7-x} (Ln=Y, Gd, Er, Yb, Lu) showed poor selectivity in the oxidative coupling of methane. The addition of 0.5 mol. %Li_{2}O to these materials considerably enhanced the yield of C_{2} hydrocarbons. This effect was related to both lower redox property and higher basicity of Li-doped catalysts as compared to those of undoped ones.
An Amperometric Biosensor For The Determination Of Organophosphorus Pesticides, Azmi Telefoncu
An Amperometric Biosensor For The Determination Of Organophosphorus Pesticides, Azmi Telefoncu
Turkish Journal of Chemistry
Organophosphorus pesticides are inhibitors of cholinesterase and this enzyme is used as a monitoring system for pesticides containing organophosphorus compounds. The decrease in activity of cholinesterase is monitored by the choline sensor and is correlated to the concentration of pesticide present in solution. According to this observation a biosensor for pesticides was determined. This biosensor consists of a Clark oxygen electrode, modified with cellulose acetate and dialysis membranes. Between the two membranes there are two immobilized enzymes: acetyl-cholinesterase and choline oxidase.
Deacidification Of High Acid Olive Oil By Immobilized Lipase, Ayşe Makasçi, Kadir Arisoy, Azmi Telefoncu
Deacidification Of High Acid Olive Oil By Immobilized Lipase, Ayşe Makasçi, Kadir Arisoy, Azmi Telefoncu
Turkish Journal of Chemistry
The acidity reduction of high acid oils prior to refining could be an attractive application for industry. In this study the enzymatic deacidification degummed and dewaxed olive oil with a high free fatty acid content, catalysed by an immobilized lipase was optimzed (Novozym 435). The optimum amount of substrate for synthesizing trigliycerides was the necessary stoichiometric amount of fatty acid and glycerol. The mixing was performed with a mechanical stirrer and the dehydration was performed by vacuum pump or by bubbling dry nitrogen. The dehydration rate was faster than the deacidification rate. The four parameters chosen for this experimental plan: …
A New Flavanone From Teucrium Alyssifolium, G. Topcu, C. Eris, S. Kurucu A. Ulubelen
A New Flavanone From Teucrium Alyssifolium, G. Topcu, C. Eris, S. Kurucu A. Ulubelen
Turkish Journal of Chemistry
From the aerial parts of {\it Teucrium alyssifolium} in addition to previously obtained {\it neo-}clerodane diterpenoids, a new flavanone alysifolinone and three flavones cirsiliol, cirsilineol and luteolin-6,7,3', 4'-tetramethyl ether, were isolated. The structure of the compounds was established by spectral data, and by TLC comparison for the known compounds. Keywords: Teucrium alyssifolium, Lamiaceae, flavanone, alysifolinone, flovones.
Adsorption Of Monovalent Cationic Dyes On Some Silicates, Oğuz İnel, Ayşegül Aşkin (Börekçi̇)
Adsorption Of Monovalent Cationic Dyes On Some Silicates, Oğuz İnel, Ayşegül Aşkin (Börekçi̇)
Turkish Journal of Chemistry
Adsorption of two cationic dyes, methylene blue (MB) and malachite green (MG), was studied on the bentonite, sepiolite and zeolite samples by the batch equilibration technique using a spectrophotometer. In addition, cation exchange capacities (CEC) of samples were determined by NH_4^{+} saturation using Kjeldhal distillation. The adsorption data was found to conform with the Langmuir equation within the concentration range studied, and Langmuir constants were determined for each of the samples. It was observed that the amount of dyes adsorbed was in excess of CEC in the case of bentonite and sepiolite. The adsorption capacities of the samples for both …
Investigation Of Adsorption Isotherms Used For Wool Dyeing By Aqueous Extraction Of Cehri Fruit (Fructus Rhamni Petiolari) And Dyeing Of Wool And Silk Accompanied By Various Mordants, A. Haluk Aydin, Fuat Güzel, Zeki Tez
Investigation Of Adsorption Isotherms Used For Wool Dyeing By Aqueous Extraction Of Cehri Fruit (Fructus Rhamni Petiolari) And Dyeing Of Wool And Silk Accompanied By Various Mordants, A. Haluk Aydin, Fuat Güzel, Zeki Tez
Turkish Journal of Chemistry
In this study, adsorption isotherms were obtained by processing wool with dyestuff solutions of different concentrations extracted from cehri fruit with water. These isotherms follow the Nernst equation; the Nernst constant was determined and interpreted. In addition, wool and silk fibres were dyed with the same dyestuff solution and various mordants. Colours having a high fastness which could be used on an industrial scale were produced.
The Effect Of Examination Stress On The Levels Of Zn^{2+}, Total Protein, Albumin In Serum And Carbonic Anhydrase Isoenzymes In Erythrocytes, Nazan Demi̇r, Yaşar Demi̇r, Ali Yildirim, Ö. İrfan Küfrevi̇oğlu, Ebubekir Bakan
The Effect Of Examination Stress On The Levels Of Zn^{2+}, Total Protein, Albumin In Serum And Carbonic Anhydrase Isoenzymes In Erythrocytes, Nazan Demi̇r, Yaşar Demi̇r, Ali Yildirim, Ö. İrfan Küfrevi̇oğlu, Ebubekir Bakan
Turkish Journal of Chemistry
In this study, the levels of Zn^{2+}, total protein and albumin in the serums of students with temporarily examination stress without any physical illnes were determined and the relationship between these values was evaluated. Furthermore, the change in the activity of carbonic anhydrase metaloenzyme with Zn^{2+} and in the rates of carbonic anhydrase I and carbonic anhydrase II were also investigated. With this aim, blood samples were taken from 100 students just before examination and from 20 control subjects. Zn^{2+} levels were determined enzymatically, while total protein and albumin assays were done with an autoanalyzer. Carbonic anhydrase activity was measured …
Synthesis Of 2,4-Dihydro-4-(2-Phenylethyl)-5-(Isomeric Pyridyl)-3h-1,2,4-Triazole-3-Thiones And Their Derivatives., Rashid Iqbal, Khosrow Zamani, Nasim H. Rama
Synthesis Of 2,4-Dihydro-4-(2-Phenylethyl)-5-(Isomeric Pyridyl)-3h-1,2,4-Triazole-3-Thiones And Their Derivatives., Rashid Iqbal, Khosrow Zamani, Nasim H. Rama
Turkish Journal of Chemistry
Intramolecular cyclization of the three isomeric 1,4-disubstituted thiosemicarbazides 3(a-c) in aqueous sodium hydroxide was attempted to obtain 2,4-dihydro-4-(2-phenylethyl)-5-(isomeric pyridyl)- 3H-1,2,4-triazole-3-thiones 4(a-c). Each of the three isolated triazoles was separately treated with benzyl chloride and with chloroacetic acid to furnish the corresponding benzylthio 5(a-c) and carboxymethylthio derivatives 6(a-c), respectively
Latex Supported Manganese(Iii) Porphyrin Catalysts For Oxidations Of Alkenes By Hydrogen Peroxide And {\It Tert-} Butyl Hydroperoxide In The Aqueous Medium, Hayrettin Türk
Turkish Journal of Chemistry
Cationic polymer latexes were prepared by emulsion copolymerization of vinylbenzyl chloride and divinylbenzene followed by quaternization with trimethylamine and used as catalyst supports for 5,10,15,20-tetrakis(2, 6-dichloro-3-sulfonatophenyl)porphinatomanganese(III) chloride and 5,10,15,20-tetra(4-sul- fonatophenyl)porphinatomanganese(III) chloride. The supported catalysts and water soluble analogues were used for oxidation of styrene, 1-decene and {\it cis}-cyclooctene by hydrogen peroxide and {\it tert}- butyl hydroperoxide in the aqueous phase. The oxidation of 1-decene and {\it cis}-cyclooctene failed. In the oxidation of styrene, the porphyrin catalysts in the latex were more active than in solution. The relative molar ratios of oxidant: styrene: Mn porphyrin were 1250: 750: 1, and about …
Synthesis, Characterization And Formation Kinetics Of Sn(Ii) And (Iv)-Schiff Base Complexes, Yakup Baran, Birgül Erk
Synthesis, Characterization And Formation Kinetics Of Sn(Ii) And (Iv)-Schiff Base Complexes, Yakup Baran, Birgül Erk
Turkish Journal of Chemistry
The synthesis and characterization of Sn(II) and Sn(IV) complexes of nitrogen and oxygen ligands, {\it p}-dimethyl aminophenylenesalicyladimine ( DPS), N,N'phenylenebis(salicylaldimine)(PBS) and N, N'-triethylenetetramine bis (salicylaldimine)(TTS) are reported. The structure of free ligands and their tin complexes were determined by elemental analysis, ir and nmr measurements. The kinetics of formation of the complexes were studied by stopped-flow technique at several temperatures with \mu=0.100 M (NaClO_{ 4}). Activation parameters \Delta H^{\ast} and \Delta S^{\ast} were determined.
Structural Fusion Of Condensed Benzenoid Systems, Lemi Türker
Structural Fusion Of Condensed Benzenoid Systems, Lemi Türker
Turkish Journal of Chemistry
On the basis of ring topologies, some theorems for the structural fusion of condensed benzenoids are presented. It has been proved that the oddness or evenness of the fused system is dictated by the degree of fusion.
Voltammetric Determination Of Promethazine By Platinum And Glassy Carbon Electrodes, Bengi Uslu, İnci Bi̇ryol, Sibel A. Özkan, Zühre Şentürk
Voltammetric Determination Of Promethazine By Platinum And Glassy Carbon Electrodes, Bengi Uslu, İnci Bi̇ryol, Sibel A. Özkan, Zühre Şentürk
Turkish Journal of Chemistry
The electrochemical oxidation of promethazine was studied by linear sweep and cyclic voltammetry on platinum and glassy carbon electrodes. The dependence of current intensities and potentials on pH, concentration, scan rate and nature of the buffer was examined. Linear calibration plots were obtained in phosphate buffer (pH 7.0) and acetate buffer (pH 4.7) for platinum and glassy carbon electrode, respectively.