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Full-Text Articles in Physical Sciences and Mathematics

An Unusual Zinc-Promoted Reductive Retro-Wagner-Meerwein Rearrangement, Yavuz Taşkesenli̇gi̇l, Metin Balci Jan 1996

An Unusual Zinc-Promoted Reductive Retro-Wagner-Meerwein Rearrangement, Yavuz Taşkesenli̇gi̇l, Metin Balci

Turkish Journal of Chemistry

Bromination and dehydrobromination of exocyclic olefin {\bf 8} resulted in the formation of bromomethylene compound {\bf 9} and Wagner-Meerwein rearrangement product {\bf 10}. The dehydrobromination of {\bf 10} with potassium {\it tert}-butoxide provided the corresponding bromomethyl compound {\bf 11} in high yield. Reaction of {\bf 11} with Zn-Cu couple in methanol afforded the methyl derivative {\bf 12} and the parent olefin {\bf 8}. The unusual formation mechanism of {\bf 8} has been discussed in term of a reductive retro-Wagner-Meerwein rearrangement.


Crystal Structure Of Tris(2-Hydroxyethyl)Ammonium Bromide, Veysel T. Yilmaz, Hasan İçbudak, Halis Ölmez, R. Alan Howie Jan 1996

Crystal Structure Of Tris(2-Hydroxyethyl)Ammonium Bromide, Veysel T. Yilmaz, Hasan İçbudak, Halis Ölmez, R. Alan Howie

Turkish Journal of Chemistry

The crystal structure of tris(2-hydroxyethyl)ammonium bromide, [HN(CH_{2}CH_{2}OH)_{3}]Br, was determined as rhombohedral by single crystal X-ray diffractometer. The final R value was found to be 0.032 for 576 observed reflections. The crystal consists of layers of hydrogen-bonded cations, [HN(CH_{2}CH_{2}OH)_{3}]^{+} and anions, Br^{-}. Within a layer every cation donates and every anion accepts three hydrogen bonds. In the cation, trifurcated intramolecular hydrogen bonds are formed due to the surrounding of the hydrogen atom bonded to the N atom by the 2-hydroxyethyl groups.


The Effect Of Metal Loading On The Adsorption Parameters Of Carbon Dioxide On Coprecipitated Nickel-Alumina Catalysts, A. Erhan Aksoylu, A. Nilgün Akin, S. Gönenç Sunol, Z. İlsen Önsan Jan 1996

The Effect Of Metal Loading On The Adsorption Parameters Of Carbon Dioxide On Coprecipitated Nickel-Alumina Catalysts, A. Erhan Aksoylu, A. Nilgün Akin, S. Gönenç Sunol, Z. İlsen Önsan

Turkish Journal of Chemistry

A coprecipitation method has been developed and modified for the preparation of nickel-alumina catalysts having metal loadings in the 0-25 wt\% Ni range. The effect of metal loading on CO_{2} adsorption was investigated under isothermal chromatographic conditions using an elution technique in the temperature range 483-533 K. Average enthalpies of adsorption were determined using the isosteres obtained from the experimental adsorption isotherms. The isotherms were also fitted to the Langmuir equation for the evaluation of adsorption equilibrium coefficients, Gibbs free energies, average adsorption enthalpies and entropies. Keywords: nickel-alumina, coprecipitated nickel-alumina, CO_{2} adsorption


The Determination Of Some Heavy Metal Cations By Tlc/Photodensitometry, Şahin Savaşçi, Mehmet Akçay Jan 1996

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 …


Extraction Of Dyestuff From Madder Plant ( Rubia Tinctorum L.) And Dyeing Of Wool, Feathered-Leather And Cotton}, Adem Önal Jan 1996

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 Jan 1996

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.


Deacidification Of High Acid Olive Oil By Immobilized Lipase, Ayşe Makasçi, Kadir Arisoy, Azmi Telefoncu Jan 1996

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: …


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 Jan 1996

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 …


Latex Supported Manganese(Iii) Porphyrin Catalysts For Oxidations Of Alkenes By Hydrogen Peroxide And {\It Tert-} Butyl Hydroperoxide In The Aqueous Medium, Hayrettin Türk Jan 1996

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 …


Analysis Of Retention In Supercritical Fluid Chromatography And Its Relation To Solubility, Z. Şermin Gönenç, Uğur Akman, Aydın K. Sunol Jan 1996

Analysis Of Retention In Supercritical Fluid Chromatography And Its Relation To Solubility, Z. Şermin Gönenç, Uğur Akman, Aydın K. Sunol

Turkish Journal of Chemistry

The effects of temperature, pressure and supercritical fluid density on the solubility-retention relationship of solutes in supercritical fluid chromatography are investigated. New retention data for naphthalene, phenanthrene, benzoic acid and 2-methoxy-naphthalene is obtained as a function of pressure at different temperatures. The bulk of the data is taken near the critical region of the mobile gas where the anomalities are expected. This data is used to compare two approaches for thermodynamic modeling of pressure dependence of solute retention. In these approaches, mobile-phase partial molar volumes of the solutes are determined either from bulk solubility data or from infinite-dilution fugacity coefficients. …


Transmission Electron Microscopy (Tem) Study Of Polycrystalline Ru:Ag/Alumina Supported Catalyst System., S. Tajammul Hussain Jan 1996

Transmission Electron Microscopy (Tem) Study Of Polycrystalline Ru:Ag/Alumina Supported Catalyst System., S. Tajammul Hussain

Turkish Journal of Chemistry

Transmission Electron Microscopy (TEM) was used to characterize bimetallic Ru/Ag Catalyst samples dispersed on a high surface area Alumina support. The addition of Ag increases the metal dispersion but no consistent trend is observed. Ag forms crystallites of various shape and sizes, some of them are present in the close vicinity of Ru but not forming Ru:Ag bimetallics. A part of Ag crystallites cover the Ru surface hence blocking Ru emission. These irregular shaped crystallites are possibly responsible for the increase in metal dispersion. Particles below 2.5 nm were Ag particles, between 2.5 to 5.0 nm were Ru:Ag mixed crystallites …


Investigation Of Acid Sites On V_{2}O_{5}/Tio_{2}(A) Catalysts By Ftir With Adsorption Of Pyridine, Ahmet Akbaş, Holger Mi̇tzel, Dieter Höni̇ce Jan 1996

Investigation Of Acid Sites On V_{2}O_{5}/Tio_{2}(A) Catalysts By Ftir With Adsorption Of Pyridine, Ahmet Akbaş, Holger Mi̇tzel, Dieter Höni̇ce

Turkish Journal of Chemistry

The V_{2}O_{5}/TiO_{2}(A) catalysts were prepared by the grafting and their Br\"{o}nsted and Lewis acid sites were investigated with pyridine adsorption by using FTIR Spectroscopy. The results obtained showed that monolayer or less coverage of the surface of the support, TiO_{2}(A), took place up to V_{2}O_{5} content of 11.88 \%. When V_{2}O_{5} amount was higher then 11.88 \%, the support was covered as multilayer. Pyridine adsorption studies showed that the number of the Lewis acid sites of the V_{2}O_{5}/TiO_{2}(A) catalysts decreased with increasing of V_{2} O_{5} amount. The number of the Br\"{o}nsted acid sites increased with increasing V_{2}O_{5} content, reached a …


Catalysis Of Autoxidation Of 2,6-Di-Tert-Butylphenol In Water By Metallophthalocyanine Tetrasulfonates Bound To Polyelectrolyte Supports, Yasemin Tura Kopkalli, Hayrettin Türk Jan 1996

Catalysis Of Autoxidation Of 2,6-Di-Tert-Butylphenol In Water By Metallophthalocyanine Tetrasulfonates Bound To Polyelectrolyte Supports, Yasemin Tura Kopkalli, Hayrettin Türk

Turkish Journal of Chemistry

2,6-and 2,10-Ionenes and soluble poly(vinylbenzyl)trimethylammonium chloride polyelectrolytes were synthesized and used as catalyst supports for cobalt-, iron- and copper-phthalocyanine tetrasulfonates on the autoxidation of 2,6-di-{\it tert}-butylphenol in water by molecular oxygen. Polyelectrolyte supported cobalt-phthalocyanine tetrasulfonate showed the highest activity in comparison with the supported analogous of iron- and copper-phthalocyanine tetrasulfonates. The supported metallophthalocyanine tetrasulfonates had better catalytic activities than the unsupported analogous for the reaction. The reaction yielded 3,3',5,5'-tetra-tert-butyl- 4,4'-diphenoquinone as the only oxidation product of 2,6-di-tert-butylphenol. The extent of the reaction was affected by time, temperature, pH, the types and concentrations of supports and metallophthalocyanine tetrasulfonates.


The Mechanism Of The Photoprotolytic Reactions Of Some Oxyazomethine Compounds, Lubov Efimovna Zelt'ser, Milan B. Bastic, Ljubinka V. Rajakovic Jan 1996

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.


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 Jan 1996

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.


A New Prodelphinine Type Alkaloid From, Ali H. Meri̇çli̇, Filiz Meri̇çli̇, Hans Becker, Ayhan Ulubelen Jan 1996

A New Prodelphinine Type Alkaloid From, Ali H. Meri̇çli̇, Filiz Meri̇çli̇, Hans Becker, Ayhan Ulubelen

Turkish Journal of Chemistry

In a previous study we have isolated five known and a new diterpenoid alkaloids from the aerial parts of {\it Aconitum nasutum}. In the present paper the structure of a new and rather rare diterpenoid alkaloid aconasutine was determined by using 1D and 2D NMR techniques.


Fixed Bed Pyrolysis And Hydropyrolysis Of An Immature Type I Turkish Oil Shale, Murat Çitiroğlu, Selma Türkay, Zeynep Işık Cepni̇, Colin Edward Snape Jan 1996

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 …


Extraction Of Dyestuff From Onion (Allium Cepa L.) And Its Application In The Dyeing Of Wool, Feathered-Leather And Cotton, Adem Önal Jan 1996

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.


A Comparison Of Adsorption Isotherms Of Crosslinked Poly(N-Vinylpyrrolidone)/Basic Brown 1 Binding System, Dursun Saraydin, Erdener Karadağ Jan 1996

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 Jan 1996

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.


An Amperometric Biosensor For The Determination Of Organophosphorus Pesticides, Azmi Telefoncu Jan 1996

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.


A Comparison Of Normal(-Cn) And Reversed (C-18) Phase Chromatographic Behaviour Of Polycyclic Aromatic Hydrocarbons, S. Fatma Aygün, Mustafa Özci̇mder Jan 1996

A Comparison Of Normal(-Cn) And Reversed (C-18) Phase Chromatographic Behaviour Of Polycyclic Aromatic Hydrocarbons, S. Fatma Aygün, Mustafa Özci̇mder

Turkish Journal of Chemistry

Because of the well-known carcinogenic and mutagenic character of polycyclic aromatic hydrocarbons (PAHs), still new methods have been tried for their qualitative and quantitative determinations in various smaples. Liquid chromatography is one of the most widely applied techniques. In this study we used liquid chromatography in normal and reversed phase modes for the determinations of PAHs and tried to find a relation between the retention times and various parameters, such as molecular shape, water solubility and number of carbon atoms.


Adsorption Of Monovalent Cationic Dyes On Some Silicates, Oğuz İnel, Ayşegül Aşkin (Börekçi̇) Jan 1996

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 Jan 1996

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.


Synthesis, Characterization And Formation Kinetics Of Sn(Ii) And (Iv)-Schiff Base Complexes, Yakup Baran, Birgül Erk Jan 1996

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.


A Novel And Stereospecific Synthesis Of Conduritol-E Via Cyclohexa-3,5-Diene-1,2-Diol, Ahmet Maras, Hasan Secen, Yasar Sütbeyaz, Metin Balci Jan 1996

A Novel And Stereospecific Synthesis Of Conduritol-E Via Cyclohexa-3,5-Diene-1,2-Diol, Ahmet Maras, Hasan Secen, Yasar Sütbeyaz, Metin Balci

Turkish Journal of Chemistry

Conduritol-E was synthesized starting from cyclohexa-3,5-diene-1,2-diol {\bf 1a} in six steps. Acetylation of the diol {\bf 1a} followed by bromination gave (2\alpha/1\beta, \,\, 3\beta, \,\, 4\beta)-1,2-dibromo-2,3- diacetoxy- 5-cyclohexene {\bf 3} as main product. KMnO_{4}-hydoxylation of the dibromide {\bf 3} followed by acetylation, Zn-elimination and hydrolysis afforded conduritol-E {\bf 5a}.


Chemistry Of Aerosol In Uludağ National Park, Serpil Y. Karakaş, Semra G. Tuncel Jan 1996

Chemistry Of Aerosol In Uludağ National Park, Serpil Y. Karakaş, Semra G. Tuncel

Turkish Journal of Chemistry

Chemical composition of aerosol samples which were collected daily during September 1993 - April 1994 was examined by determining the concentrations and variations of major ions in aerosol samples, determining the binary correlations and the sources of them. Sulfate made up the 30% of aerosol mass with an 2.14 \mug m^{-3} average concentration. Measured chemical parameters in Uludağ National Park were comparable with other rural area data expect Ca^{2+} which was higher in our station with an average concentration of 1.61 \mug m^{-3}. Ion balance showed a deficiency of acid forming anions (SO^{2-}_4 and NO^-_3 for about 30% on the …


The Epoxidation Of Oil Obtained From The Eastern Black Sea Fishes, Eyüp Özcan, Bahri Ülküseven Jan 1996

The Epoxidation Of Oil Obtained From The Eastern Black Sea Fishes, Eyüp Özcan, Bahri Ülküseven

Turkish Journal of Chemistry

In this study we have investigated the suitable reaction conditions for the epoxidation of the semi-refined fish oil obtained from the fishes of eastern Black Sea, with peracetic acid. Various oxidation mixtures to reach the highest epoxyd-oxygene amount have been tested mean while the effective factors were established. In order to establish some specifications of the epoxy-product. Iodine-, hydroxyl-indices and epoxyd-oxygene percents were determined. We've also tried to explain how some reaction conditions (mole ratio of acetic acid to double bond and temperature) influenced the epoxy-product.