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Articles 2611 - 2640 of 2730
Full-Text Articles in Physical Sciences and Mathematics
Potentiometric Investigation Of The Effects Of Several Substituents On The Basicity Of Benzilidene-O-Hydroxyaniline, Esma Kiliç, Orhan Atakol, E. Canel, Zehra Ali̇beşeoğlu, Turgut Gündüz, Fitnat Köseoğlu
Potentiometric Investigation Of The Effects Of Several Substituents On The Basicity Of Benzilidene-O-Hydroxyaniline, Esma Kiliç, Orhan Atakol, E. Canel, Zehra Ali̇beşeoğlu, Turgut Gündüz, Fitnat Köseoğlu
Turkish Journal of Chemistry
Chloro-, bromo-, iodo-, nitro-, methoxy- and hydroxy-substituted benzilidene-o-hydroxyaniline were prepared in order to investigate the effects of substituents on the basicity of benzilidene-o-hydroxyaniline. For each substituent, three isomers -- ortho, meta and para -- were synthesised. Schiff bases were titrated potentiometrically with perchloric acid in nitrobenzene solvent at $25^{\circ}$C. All compounds gave well-shaped titration curves, from which half-neutralisation potentials were calculated. The trend in the values of half-neutralisation potentials of Schiff bases were explained in terms of the nature of the substituents. The applicability of the Hammett equation to the effect of substituents in Schiff bases in nitrobenzene solvent was …
On The Türker Angles In The Theory Of Total \Pi-Electron Energy, Ivan Gutman
On The Türker Angles In The Theory Of Total \Pi-Electron Energy, Ivan Gutman
Turkish Journal of Chemistry
The Türker angles $\theta, \alpha$ and $\beta$ are quantities invented by Lemi Türker, and are used in the theory of total $\pi$-electron energy $(E)$ of unsaturated conjugated hydrocarbons. We report here expressions for $\theta, \alpha$ and $\beta$ in terms of $E$ and the parameters $n$ (= half the number of carbon atoms) and $e$ (= the number of carbon-carbon bonds). The forms of these expressions are remarkably similar. Numerical calculation performed on a representative set of benzenoid hydrocarbons reveals that the dependence of the angles $\alpha$ and $\beta$ on molecular structure is very similar, and that their ratio is almost …
Thermal Behaviour Of Some Azo Dyes Containing Sterically Hindered And Water-Soluble Groups, Hasan Kocaokutgen, Zerrin Heren
Thermal Behaviour Of Some Azo Dyes Containing Sterically Hindered And Water-Soluble Groups, Hasan Kocaokutgen, Zerrin Heren
Turkish Journal of Chemistry
Thermal behaviour of six azo dyes containing steric hindered groups such as tert-butyl, sec-butyl and isopropyl, were investigated by means of thermogravimetry (TG), differential thermal analysis (DTA) and differential thermogravimetry (DTG). The thermal decomposition points and amount of volatile pyrolysis products, were determined in nitrogen atmosphere using TG, DTA and DTG curves.
Crystal And Molecular Structure Of Tris(2,6-Dichlorophenyl) Thiophosphate, Veysel T. Yilmaz, Mustafa Odabaşoğlu, R. Alan Howie
Crystal And Molecular Structure Of Tris(2,6-Dichlorophenyl) Thiophosphate, Veysel T. Yilmaz, Mustafa Odabaşoğlu, R. Alan Howie
Turkish Journal of Chemistry
The crystal structure of tris(2,6-dichlorophenyl)thiophosphate was determined by single crystal X-ray diffractometry. The structure consists of isolated molecules and each unit cell contains 8 molecules of the compound. The crystal system is monoclinic with a space group of C2/c. The P atom is bonded to three O atoms and one S atom in a distorted tetrahedron environment.
Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain
Kinetic Studies Of The Thermal Decomposition Of Di- And Tri-Organotin Derivatives Of 1-Nitroso-2-Naphthol, Saqib Ali, Moazzam H. Bhatti, Sohail Mahmood, Muhammad Mazhar, M. Saleem Khalid, Nazar Hussain
Turkish Journal of Chemistry
The di- and tri-organotin complexes of general formula R$_2$SnL$_2$ and R$_3$SnL where R = C$_4$H$_9$, C$_6$H$_5$, C$_6$H$_5$CH$_2$, C$_6$H$_{11}$ and L=1-nitroso-2-naphthol, were subjected to thermal decomposition by means of thermogravimetry (TG). The decomposition occurred in steps and the kinetics of every set of reactions were determined using the method described by Coats and Redfern. These results were analysed to establish the decomposition kinetics and hence to calculate activation energies. The activation energies were also determined by applying the method described by Horowitz, which yielded comparable results.
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.
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 …
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.
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 …
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 …
Kinetics Of Autoxidative Polymerization Of Sunflowerseed Oil, Hüseyin Topallar, Yüksel Bayrak, Mehmet İşcan
Kinetics Of Autoxidative Polymerization Of Sunflowerseed Oil, Hüseyin Topallar, Yüksel Bayrak, Mehmet İşcan
Turkish Journal of Chemistry
The rates of polymerization of unhydrogenated and hydrogenated sunflowerseed oils were measured under atmospheric conditions in the various containers (glass, PET and metal). Polymerization rates showed a strong dependence on the degree of unsaturation and the light transmittance of the containers. The average molecular weights of polymerized oils were determined by viscosity measurements.The relationship between viscosity and average molecular weight was determined. It is seen that unhydrogenated sunflowerseed oil has a higher polymerization rate than hydrogenated oil samples in a glass container and they has higher viscosity values.
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 …
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 …
Apocarbonic Anhydrase-Enzymatic Determination Of Zinc In Fruit Juices, Ayşe Karagölge, Nazan Demi̇r, Yaşar Demi̇r, İrfan Küfrevi̇oğlu
Apocarbonic Anhydrase-Enzymatic Determination Of Zinc In Fruit Juices, Ayşe Karagölge, Nazan Demi̇r, Yaşar Demi̇r, İrfan Küfrevi̇oğlu
Turkish Journal of Chemistry
In this study, a new enzymatic method for determining trace amount of zinc was employed on ten different fruit juices. The basis of the enzymatic method is that apocarbonic anhydrase regains its activity in proportion to the Zn^{2+} existing in a solution. Thus, the more activated the enzyme is in the medium, the higher the Zn^{2+} concentration in the solution will be. For this purpose, bovine carbonic anhydrase was purified from erythrocyte hemolisate by affinity chromatography. The Zn^{2+} bound to the enzyme was removed by of the purified enzyme against the solution of pyridine-2-6-dicarboxylic acid. Thus 100\% purified enzyme was …