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Reduction Of Combustion Generated Pollution: Process Modifications And Energy Efficient Power Cycles, Janos M. Beer
Reduction Of Combustion Generated Pollution: Process Modifications And Energy Efficient Power Cycles, Janos M. Beer
Turkish Journal of Chemistry
Theoretical bases of combustion process modifications aimed at the reduction of pollutant emission are examined. It is shown, as an example, of how the minimization of emissions of nitrogen oxides leads to a design protocol that translates results of modeling and of bench scale experiments into guidelines for industrial design. The formation and emission of polycyclic aromatic compounds is also considered, because their formation is strongly favored in "low NO_x flames". In power generation the pollutant emission can be reduced effectively by the improvement of the ``heat rate,"i.e., the thermodynamic efficiency of the power cycle. Combined gas turbine-steam cycles which …
Novel Architectures Of Macromolecular Systems, Gerhard Wegner
Novel Architectures Of Macromolecular Systems, Gerhard Wegner
Turkish Journal of Chemistry
An important thrust in modern macromolecular chemistry is to construct complex architectures either directly from monomer units, or to design macromolecules capable of forming a desired superstructure by self-organization. Chain-rigidity is an example of a structural principle leading to self organization depending on the aspect ratio of the molecular objects and their mutual interactions. These molecularly defined objects serve as the building blocks of systems for which ultrathin layers composed of hairy rod macromolecules (HRM) are an example. Depending on architectural details layered architectures of HRM are models for molecular nanocomposites, exhibit interesting optical, electrochemical, dielectric or barrier properties. They …
Polymer Light Emitting Diodes, Frank E. Karasz, Bin Hu, Zhou Yang
Polymer Light Emitting Diodes, Frank E. Karasz, Bin Hu, Zhou Yang
Turkish Journal of Chemistry
Polyphenylene vinylene-based conjugated-nonconjugated alternating block copolymers form the active chromophores in a series of light emitting diodes (LEDs). The quantum efficiency and brightness of these devices can be improved by several orders of magnitude by incorporation of appropriate carrier transport layers and by rational choice of electrodes. Further improvements can be gained by blending of the active chromophores with high or low molecular weight species.
Antifungal Natural Products From Medicinal Plants Of Pakistan, Atta Rahman, M. I. Choudhary
Antifungal Natural Products From Medicinal Plants Of Pakistan, Atta Rahman, M. I. Choudhary
Turkish Journal of Chemistry
A number of diseases in humans, animals, insects and plants are caused by pathogenic fungi. Several fungi also produce toxins in foods and can cause poisoning. Antifungal compounds are therefore important both for controlling serious fungal diseases of animals and plants, and for preserving food and other organic materials against attack by fungi. Our work on antifungal phytochemicals of medicinal plants has resulted in the isolation of a number of interesting compounds. The agar diffusion method was used to determine the antifungal activity of the pure isolates and extracts against a number of highly pathogenic fungi. The structures of the …
Analytical Applications Of Organic Conducting Polymer Electrodes, Nada F. Atta, George C. Russell, Z. Wang, N. Akmal, J.F. Rubinson, S.K. Lunsford, E. Karagözler, O. Y. Ataman, H. Zimmer, H.B. (Jr.) Mark, Ahmed Galal
Analytical Applications Of Organic Conducting Polymer Electrodes, Nada F. Atta, George C. Russell, Z. Wang, N. Akmal, J.F. Rubinson, S.K. Lunsford, E. Karagözler, O. Y. Ataman, H. Zimmer, H.B. (Jr.) Mark, Ahmed Galal
Turkish Journal of Chemistry
Electrodes modified by he electrodeposition of conducting polymers were used for the detection and quantitative determination of some inorganic, organic, and biological molecules. Monomers used were five membered ring heterocycles or crown ethers and their derivatives. The polymer films were deposited on glassy carbon or platinum substrates. The resulting electrodes were used in the amperometric mode or in the potentiometric mode for flow injection and chromatographic analyses. The results showed that the proposed modified surface catalyzes the oxidation of organic and biological compounds. The detection of electroinactive inorganic anions, such as F^-, Cl^-, Br^-, NO_2^- and NO^-_3 was also possible …
Synthesis And Characterization Of Conducting Polymers And Their Composites, L. Toppare
Synthesis And Characterization Of Conducting Polymers And Their Composites, L. Toppare
Turkish Journal of Chemistry
Blends of conducting polymers polypyrrole and polyaniline, in the insulating host polymers, polybisphenol A carbonate, polyamide and polyamide have been prepared electrochemically. Composite homogeneity and a possible chemical interaction between the host matrices and the conducting polymers were searched. Several spectroscopic and thermal analyses of free standing films suggest such an interaction.
Dissociation Dynamics Of Small Carbon Clusters, Ersin Yurtsever, Nuran Elmaci
Dissociation Dynamics Of Small Carbon Clusters, Ersin Yurtsever, Nuran Elmaci
Turkish Journal of Chemistry
The dissociation dynamics of small carbon clusters is studied by classical trajectory analysis. A large number of initial conditions are chosen to analyze the effects of the energy, angular momentum and the initial geometry of the cluster. The dissociation times, decay rate constants, kinetic energy of the dissociating atoms and the geometrical structure of the remaining part of the clusters are computed from microcanonical sampling of the phase space. Distributions of these properties as well as the possibilities of various fragmentation channels are presented.
A Computational Study On The Conformational Behaviour Of 1,1,2-Trihydroxyethane In Solution, Safiye Sağ Erdem, Tereza Varnali, Viktorya Avi̇yente
A Computational Study On The Conformational Behaviour Of 1,1,2-Trihydroxyethane In Solution, Safiye Sağ Erdem, Tereza Varnali, Viktorya Avi̇yente
Turkish Journal of Chemistry
The conformational space of 1,1,2-trihydroxyethane were investigated with the PM3 method both in gas phase and in solution. Ab initio calculations at 6-31G level were also conformational equilibria in solution were studied and used to explain the behaviour of 2-hydroxycyclohexanone propylene and ethylene ketals.
General Character Of Electrochaemically Adsorbed Cobalt On Smooth Platinum In Solutions Of Various Ph, Gülcemal Yildiz, Sadiq Kuluyev, Figen Kadirgan
General Character Of Electrochaemically Adsorbed Cobalt On Smooth Platinum In Solutions Of Various Ph, Gülcemal Yildiz, Sadiq Kuluyev, Figen Kadirgan
Turkish Journal of Chemistry
The adsorption of cobalt adatoms on to a smooth platinum electrode at different potentials was studied by voltammetric methods. The amount of cobalt coverage was determined from the hydrogen region of the platinum electrode. The number of electrons per adatom species was calculated. The experiments were carried out in the pH interval between 0-3 in H_{2}SO_{4}-containing solutions.
Synthesis And Characterization Of Complexes Of Co(Ii), Ni(Ii), Cd(Ii), Hg(Ii) And Pd(Ii) With Some N-Phenyl-N^{1}-2-[4-Phenyl-(Substituted) Thiazolyl]- Thioureas, B. Narayana, M. R. Gajendragad
Synthesis And Characterization Of Complexes Of Co(Ii), Ni(Ii), Cd(Ii), Hg(Ii) And Pd(Ii) With Some N-Phenyl-N^{1}-2-[4-Phenyl-(Substituted) Thiazolyl]- Thioureas, B. Narayana, M. R. Gajendragad
Turkish Journal of Chemistry
The Synthesis and characterization of the complexes of Co(II), Ni(II), Pd(II), Cd(II) and Hg(II) with N-phenyl-N^{1}-2(-4-phenylthiazoly)thiourea (PPT) and N-phenyl-N^{1}-2-(4-methylphenylthiazolyl)-thiourea (PMPT) and Co(II), Cd(II), and Hg(II) complexes of N-phenyl-N^{1}-2-(4-p- chlorophenylthiazolyl) thiourea (PCPT) are included in this paper. Based on analytical results, electronic and infrared spectral data and magnetic susceptibility measurements, plausible structures have been proposed.
Complexes Of Zn(Ii), Pd(Ii), Hg(Ii), Pb(Ii), Cu(I), Ag(I) And Tl(I) With 4-Amino-5-Mercapto-3-(O-Tolyloxymethyl)-1,2,4-Triazole, B. Narayana, M. R. Gajendragad
Complexes Of Zn(Ii), Pd(Ii), Hg(Ii), Pb(Ii), Cu(I), Ag(I) And Tl(I) With 4-Amino-5-Mercapto-3-(O-Tolyloxymethyl)-1,2,4-Triazole, B. Narayana, M. R. Gajendragad
Turkish Journal of Chemistry
The synthesis and characterization of complexes of Zn(II), Pd(II), Cd(II), Hg(II), Pb(II), Cu(I), Ag(I), and Tl(I) with 4-amino-5-mercapto-3-(o- tolyloxymethyl)-1,2,4-triazole are described. Based on analytical results, electronic and infrared spectral data and magnetic susceptibility measurements suitable structures have been proposed.
Carbon Monoxide Hydrogenation Over Ru-Mn-K/Al_2o_3 Catalysts, S. Tajammul Hussain, M. Ashraf Atta
Carbon Monoxide Hydrogenation Over Ru-Mn-K/Al_2o_3 Catalysts, S. Tajammul Hussain, M. Ashraf Atta
Turkish Journal of Chemistry
The catalytic behavior of a series Ru/Al_2O_3 catalysts promoted with various levels of Mn and K prepared by coimpregnation were investigated in the CO-hydrogenation reaction. Catalytic studies showed that the addition of Mn enhances the production of Fischer Tropsch products and K promotion in particular enhances the production of unsaturated hydrocarbons while inhibiting the methanation reaction. The influence of K and Mn on the Fischer Tropsch product selectivity in CO-hydrogenation studies is discussed in terms of ensemble and electronic effects, and the production of a new surface site Ru:Mn:K.
Topological Constraints On Hmo Hetereoatom Parameters, Lemi Türker
Topological Constraints On Hmo Hetereoatom Parameters, Lemi Türker
Turkish Journal of Chemistry
Within the Hückel molecular orbital framework, the effect of topological factors on the selection of heteroatom parameters for heteroconjugated systems is discussed.
Factors Influencing The Angle Of Total Ii-Electron Energies Of Alternant Hydrocarbons, Lemi Türker
Factors Influencing The Angle Of Total Ii-Electron Energies Of Alternant Hydrocarbons, Lemi Türker
Turkish Journal of Chemistry
Within the framework of the Hückel molecular orbital theory, the topological factors affecting the angle of total \pi-electron energies of alternant hydrocarbons were investigated.
Ion Chromatographic Analysis Of Water-Soluble Anions In The Atmosphere In Amman, Jordan, Qasem M. Jaradat, Kamal A. Monami, Anwar G. Jiries
Ion Chromatographic Analysis Of Water-Soluble Anions In The Atmosphere In Amman, Jordan, Qasem M. Jaradat, Kamal A. Monami, Anwar G. Jiries
Turkish Journal of Chemistry
In the summer of 1995, samples of airborne particles were collected in the Amman area of Jordan. Ion chromatography (IC) was used for the determination of anions in these samples. Four anions were identified and quantified in the atmosphere of Amman. The concentration ranges of F^-, CL^-, NO_3^- and SO_4^= were 0.04 - 3.3, 2.25 - 15.7, 1.96 - 8.39 and 16.88 - 41.33 \mug/m^3, respectively. The study shows that Cl^-, NO_3^-, and SO_4^= are the major anions of air particulate, and the concentration of SO_4^= exceeds that of some other cities worldwide. The total suspended particles (TSP) value was …
Controlled Release Of Aldicarb From Carboxymethylcellulese Microcapsules, M. Yakup Arica, Mustafa Yi̇ği̇toğlu, Mustafa Lale, Fatma N. Kök, Vasıf Hasirci
Controlled Release Of Aldicarb From Carboxymethylcellulese Microcapsules, M. Yakup Arica, Mustafa Yi̇ği̇toğlu, Mustafa Lale, Fatma N. Kök, Vasıf Hasirci
Turkish Journal of Chemistry
Sodium carboxymethyl cellulose was converted into microspheres by crosslinking with aluminum chloride. Various microsheres with different amounts of crosslinker, biopolymer of various concentrations and molecular weights, and with different pesticide (Aldicarb) contents and pesticide to polymer ratios were prepared. The pesticide encapsulation efficiencies and aldicarb release kinetics of the resultant microcapsules were investigated. It was possible to modify the release behaviour by varying the above parameters and to have drug release with half-lives longer than 100 hours in aqueous media. The release kinetics were described by first order and zero order kinetics.
Spectrophotometric Determination Of The Pk_A Values Of Some Aminoacid Complexes Of Pentacyanoferrate(Ii) And Pentacyanoruthenate(Ii), Yakup Baran, Şebnem Baran, N. Kemal Tunali
Spectrophotometric Determination Of The Pk_A Values Of Some Aminoacid Complexes Of Pentacyanoferrate(Ii) And Pentacyanoruthenate(Ii), Yakup Baran, Şebnem Baran, N. Kemal Tunali
Turkish Journal of Chemistry
The syntheses, pK_a and spectrospcopic characterization of [Fe(CN)_5(H_2O)]^{-3} and [Ru(CN)_5(H_2O)]^{-3} complexes of alanine(Ala), glycine(Gly), valine(Val), lysine(Lys), arginine(Arg) and cysteine(Cys) complexes were investigated in aqueous solution. The spectra of the complexes containing amino acid ligands were similar to that of [Fe(CN)_5(NH_3)]^{-3}. The pK_a values of the complexes were measured by spectrophotometric titration at 22^{\circ}C and \mu =0.100 M(NaClO_4).
Carbonic Anhydrase From Nicotiana Tabacum Leaves, Nazan Demi̇r, Yaşar Demi̇r
Carbonic Anhydrase From Nicotiana Tabacum Leaves, Nazan Demi̇r, Yaşar Demi̇r
Turkish Journal of Chemistry
In this study, carbonic anhydrase (CA: carbonate hydrolyase; E.C.4.2.1.1) was purified from adult {\it Nicotiana tabacum} leaves and studied biochemically. The enzyme was purified twice times by using (NH$_4)_2SO_4 precipation and DEAE-cellulose column chromatography, and its activity was determined for two different substrates (CO_2 and p-nitrophenyl acetate). The enzyme obtained from the ion exchange column was purified 40.7 fold and the purity was controlled by 3\%-10\% discontinuous SDS-PAGE. The pH of the purified enzyme varied between 6.0 and 7.2, the optimum being 6.9. V_{max} and K_m values were calculated with p-nitrophenyl acetate (0.1524 mM, 0.5446 mM, respectively) as substrate. The …
Examination Of Historical Textiles With Dyestuff Analyses By Tlc And Derivative Spectrophotometry, Recep Karadağ, Emre Dölen
Examination Of Historical Textiles With Dyestuff Analyses By Tlc And Derivative Spectrophotometry, Recep Karadağ, Emre Dölen
Turkish Journal of Chemistry
A group of historical textiles in the Topkapi Museum, i.e., silk brocades classified as 16th century pieces by art historians, were investigated by TLC and spectrophometric analyses of their dyestuffs for the purpose of dating these pieces. The dyestuffs contained intextile fibers were extracted with acid solutions of varying strength, and the acid extracts were analyzed by both TLC and spectrophotometry, either directly or after an organic solvent extraction step. The first derivative spectra proved to provide more information than the main spectra. In order to eliminate possible interferences in spectrophotometry arising from impurities in the fibers, e.g., compounds containing …
Electron Spin Resonance Studies On Cobalt Carbonic Anhydrase-Substrate Complexes, Çigdem Nuhoğlu, Nazan Demi̇r, Barbaros Nalbantoğlu, Ö. İrfan Küfrevi̇oğlu, Y. Kemal Yoğurtçu, Hasan Özdemi̇r, Enise Ayyildiz
Electron Spin Resonance Studies On Cobalt Carbonic Anhydrase-Substrate Complexes, Çigdem Nuhoğlu, Nazan Demi̇r, Barbaros Nalbantoğlu, Ö. İrfan Küfrevi̇oğlu, Y. Kemal Yoğurtçu, Hasan Özdemi̇r, Enise Ayyildiz
Turkish Journal of Chemistry
The native zinc atom of bovine erythrocyte carbonic anhydrase purified by affinity choromatography was removed by dialysis against pyridine 2,6-dicarboxylic acid. Cobalt carbonic anhydrase was prepared from the zinc-free apoenzyme. The binding conditions of CO_2 and p-nitrophenylacetate to cobalt carbonic anhydrase were investigated by electron spin resonance at different pH levels.
A Novel Glycosidicly Linked Piperidine Alkaloid From Cyclamen Coum, Nurettin Yayli, Cemalettin Baltaci
A Novel Glycosidicly Linked Piperidine Alkaloid From Cyclamen Coum, Nurettin Yayli, Cemalettin Baltaci
Turkish Journal of Chemistry
The structure of a novel piperidine type alkaloid from {\it Cyclamen coum} was established as 2-\beta-D-glycopyranosyl-2-undecil-3,5-dihydroxy-6-carboxypiperidine, {\bf 1,} whose structure has been deduced from spectral data.
A Quantum-Chemical Investigation On 3-(4h-1,2,4-Triazol-4-Yl)-1h-1,2,4-Triazole, Rıza Abbasoğlu, Necdet Saltek, A. Aykut İki̇zler
A Quantum-Chemical Investigation On 3-(4h-1,2,4-Triazol-4-Yl)-1h-1,2,4-Triazole, Rıza Abbasoğlu, Necdet Saltek, A. Aykut İki̇zler
Turkish Journal of Chemistry
The molecular conformations and electronic properties of the 3-(4H-1,2,4-triazol-4-yl)-1H-1,2,4-triazole molecule containing various reaction centers were investigated by the semiempirical methods MNDO, AM1 and PM3. The most stable conformation of the molecule was determined to be the planar conformation. The total energies, heats of formation, dipole moments, rotational barriers, geometric parameters, ionization potentials, full atomic charges, energies of frontier molecular orbitals (E_{HOMO} and E_{LUMO}) and their electron densities were calculated and discussed. In order to determine the protonation sites of the 3,4'-bitriazole system, the molecular electrostatic potential (MESP) of the molecule has also been calculated. The conformations and electronic properties of …
Catalytically Active Intermediates In Photochemical Metathesis, Çetin Bozkurt, Yavuz İmamoğlu
Catalytically Active Intermediates In Photochemical Metathesis, Çetin Bozkurt, Yavuz İmamoğlu
Turkish Journal of Chemistry
The nature of the active species in photocatalytic metathesis reaction was investigated. The formation of Wittig-type addition products with benzaldehyde indicates that catalytically active carbene is the product of olefin and tungsten hexacarbonyl under reaction conditions.
Influence Of Some Crosslinkers On The Swelling Of Acrylamide-Crotonic Acid Hydrogels, Erdener Karadağ, Dursun Saraydin, Olgun Güven
Influence Of Some Crosslinkers On The Swelling Of Acrylamide-Crotonic Acid Hydrogels, Erdener Karadağ, Dursun Saraydin, Olgun Güven
Turkish Journal of Chemistry
Acrylamide-crotonic acid hydrogels in the form of rods are prepared by \gamma-irradiation of quaternary mixtures of acrylamide-crotonic acid-crosslinker-water with 2.6 and 5.2 kGy \gamma-rays. The influence of the applied dose, the relative content of crotonic acid and crosslinkers such as ethylene glycol dimethacrylate, 1.4 butanediol dimethacrylate and N,N' methylenebisacrylamide on the swelling properties of the gel, the diffusional behaviour of water, the diffusion coefficient, and the network parameters of hydrogel systems are examined. Acrylamide-crotonic acid hydrogels containing various crosslinkers had a maximum swelling in the range 240-850 \%. Water diffusion to hydrogels was non-Fickian. The diffusion coefficients varied between 4.6 …
Epr Spectroscopy Of Dog-Rose Polyphenoloxidase, Çiğdem Nuhoğlu, Fatih Ucun, Enise Ayyildiz, Y. Kemal Yoğurtçu, Halis Şaki̇roğlu, İrfan Küfrevi̇oğlu
Epr Spectroscopy Of Dog-Rose Polyphenoloxidase, Çiğdem Nuhoğlu, Fatih Ucun, Enise Ayyildiz, Y. Kemal Yoğurtçu, Halis Şaki̇roğlu, İrfan Küfrevi̇oğlu
Turkish Journal of Chemistry
Polyphenoloxidase(PPO) of dog-rose fruit was extracted and purified through (NH\4)\2SO\4 precipitation and dialysis. The optimum conditions for this purpose, i.e., pH and temperature, were determined with 4-methylcatechol optimum pH and temperature and found to be pH 8.5 and 20\ci, respectively. The inhibition effect of ascorbic acid was investigated and the I_{50} value was found to be 1.57\times10^{-4} M. The activity of dog-rose PPO was investigated by electron paramagnetic resonance (EPR) at different pH levels and temperatures. The optimum conditions obtained from both spectrophotometry and EPR were compared.
The Synthesis Of Some Novel Chromans, M. Yalçinkaya, O. Bi̇lgi̇ç, S. Bi̇lgi̇ç
The Synthesis Of Some Novel Chromans, M. Yalçinkaya, O. Bi̇lgi̇ç, S. Bi̇lgi̇ç
Turkish Journal of Chemistry
The inverse-electron demanded Diels-Alder reaction of 1-N,N-dimethylaminomethyl-2-naphthol (1) with substituted styrenes were investigated. With 2-, 3-, 4-methylstyrenes, 2-(2'-,3'- and 4'-methylphenyl)-benzo-5,6-chromans (5, 6 and 7) were obtained in 12, 18 and 53 \% yields respectively. With 2-, 3- and 4-chlorostyrenes, 2-(2'-, 3'- and 4'-chlorophenyl)-benzo-5,6-chromans (8,9 and 10) were obtained in 8, 20 and 33 \% yields respectively. With 4-vinyl-pyridine, 2-($4'-pyridyl)-benzo-5,6-chroman (11) was obtained in 48\% yield. In all pyrolysis no quinone-methide dimer (4) was encountered.
Some Oxidation Reactions Of Isomeric Pyridinecarboxylic Acid Hydrazides, Rashid Iqbal, Samia Ebrahim, Muhammad Ziaulhaq
Some Oxidation Reactions Of Isomeric Pyridinecarboxylic Acid Hydrazides, Rashid Iqbal, Samia Ebrahim, Muhammad Ziaulhaq
Turkish Journal of Chemistry
The oxidation reactions of the three isomeric pyridinecarboxylic acid hydrazides were studied using sodium metaperidoate, silver(I) oxide and potassium ferricyanide separately. Potassium ferricyanide emerged as an excellent reagent for preparation of 2-pyridinecarboxaldehyde and 3-pyridinecarboxaldehyde from the respective isomeric pyridinecarboxylic acid hydrazides. Oxidation with silver(I) oxide in each case yielded the corresponding 1,2-dipyridoylhydrazine, while sodium metaperiodate furnished different products with each isomeric pyridinecarboxylic acid hyrazide.
Determination Of Ponceau 4r And Tartrazine In Various Food Samples By Derivative Spectrophotometric Methods, Sedat Sayar, Yüksel Özdemi̇r
Determination Of Ponceau 4r And Tartrazine In Various Food Samples By Derivative Spectrophotometric Methods, Sedat Sayar, Yüksel Özdemi̇r
Turkish Journal of Chemistry
Derivative spectrophotometric methods were originally developed for determining Ponceau 4R and Tartrazine in order to resolve their binary mixtures. The method permits the simultaneous determinations of these food colorants in various food samples. Recovery by derivative methods was nearly 100 \%.
Effect Of Various Additives On The Hydration Of Perlite-Gypsum Plaster And Perlite-Portland Cement Pastes, Emin Erdem
Effect Of Various Additives On The Hydration Of Perlite-Gypsum Plaster And Perlite-Portland Cement Pastes, Emin Erdem
Turkish Journal of Chemistry
Perlite is a volcanic glass which forms a light-weight cellular aggregate when ground and heated to about 1000\ci. It is used in the production of light-weight masonry blocks and concrete in the building industry as well as in insulation, fire protection, agriculture and pharmacology. In this study, the effects of admixtures such as lime, sodium citrate and various superplasticizers on the hydration of perlite-gypsum plaster, perlite-white Portland cement and perlite-blended Portland cement mixtures were investigated by measurement of flexural and compressive strengths and by DTA-TG. It was found that the addition of lime caused pozzolanic reactions and, consequently, increased strength …
Thermodynamics Of Dissociation Of Strontium, Barium And Nickel Caproates In Water, Hüseyin Topallar, Yüksel Bayrak, Mehmet İşcan
Thermodynamics Of Dissociation Of Strontium, Barium And Nickel Caproates In Water, Hüseyin Topallar, Yüksel Bayrak, Mehmet İşcan
Turkish Journal of Chemistry
The critical micellar concentration (CMC) and thermodynamic parameters (heat \DeltaH_d, free energy \DeltaG_d, and entropy \DeltaS_d, of dissociation) of aqueous solutions of strontium, barium and nickel caproates were determined by conductivity measurements. A Kraus and Bray-type expression was used to evaluate molecular conductance at infinite dilution and theromdynamic parameters. The results confirm that CMC remains unaffected by temperature in the range of 25-55^{\circ}C, and show that the dissociation of soaps is an exothermic reaction and nonspontaneous.