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Full-Text Articles in Physical Sciences and Mathematics

Study Of Interaction And Solubility Parameters Of Alkyl Methacrylate Polymers By Inverse Gas Chromatography, İsmet Kaya, Eyüp Özdemi̇r, Mehmet Coşkun Jan 1996

Study Of Interaction And Solubility Parameters Of Alkyl Methacrylate Polymers By Inverse Gas Chromatography, İsmet Kaya, Eyüp Özdemi̇r, Mehmet Coşkun

Turkish Journal of Chemistry

Flory-Huggins interaction parameters (\chi) and partial molar free energies of mixing (\DeltaG^{\infty}_1) have been determined by inverse gas chromatography (i.g.c.) at temperatures 413-443 K for alkanes, acetates, ketones, aromatics, THF and methanol to estimate the polymer solubility parameters (\delta_2) of PMMA, PEMA, PİBMA and Pt-BMA. Furthermore, weight fraction activity coefficients (\alpha_1/W_1)^{\infty} of probes were calculated at infinite dilution at 413-443 K.


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. …


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


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 …


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 Effects Of Polyacrylic Acid/Polypyrrole Composite Coating On Photocorrosion And Photoactivity Of Pyrite Electrodes, A. Sezai Saraç, Belkıs Ustamehmetoğlu, Esma Sezer, Candan Erbi̇l Jan 1996

The Effects Of Polyacrylic Acid/Polypyrrole Composite Coating On Photocorrosion And Photoactivity Of Pyrite Electrodes, A. Sezai Saraç, Belkıs Ustamehmetoğlu, Esma Sezer, Candan Erbi̇l

Turkish Journal of Chemistry

Electrically conducting polyacrylic acid (PAA)/Polypyrrole (PPy) composite films were prepared by electrochemical polymerization of pyrrole on PAA which was electrocheimically adsorbed on natural and synthetic pyrite ( FeS_{2}) electrodes. The application of such polymer coating on pyrite, which is one of the semiconducting materials for solar applications, shows almost total protection against corrosion and can improve the photoactive character of the electrode. Addition of Ce(IV) ammonium nitrate into this system improved the photoactivity of the PAA/PPy composite. The composite polymer has higher photoconductivity than the pure PPy, because of the doping effect of anions on the PPA/PPy composite.


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.


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.


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 …


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.


The Sterols Of Cyclamen Coum, Nurettin Yayli, Cemalettin Baltaci Jan 1996

The Sterols Of Cyclamen Coum, Nurettin Yayli, Cemalettin Baltaci

Turkish Journal of Chemistry

The structures of one major and three minor constituents of sterol fraction of the Cyclamen coum have been established as stigmasterol [(22E)- (24S)- 24-ethylcholesta-\Delta ^{5,22}-dien-\beta-ol] ({\bf 1}), Poriferasterol [22E)-(24R)-24-ethylcholesta-\Delta^{5,22}-dien-3\beta- ol] ({\bf 2}), stigma-or poriferasta-\Delta^{3,5,22} triene [(22E)-24 -ethylcholesta-\Delta^{3,5,22}-trien] ({\bf 3}) stigma-or poriferosta- \Delta^{3,5,7,22}-tetraene [(22E)-24-ethylcholesta-\Delta^{3,5,7,22}- tetraene] ({\bf 4}) by spectroscopic means (NMR, EI-MS and GC-MS).


A New Flavanone From Teucrium Alyssifolium, G. Topcu, C. Eris, S. Kurucu A. Ulubelen Jan 1996

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.


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 …


The Investigation Of Aluminum Sulfate-Potassium Chloride Solid Phase Reaction, İ. Ayhan Şengi̇l Jan 1996

The Investigation Of Aluminum Sulfate-Potassium Chloride Solid Phase Reaction, İ. Ayhan Şengi̇l

Turkish Journal of Chemistry

It was found that aluminum sulfate reacts with potassium chloride to produce K_{2}SO_{4}, Al_{2}O_{3}, and Cl_{2} in the solid phase at 700 ^{\circ}C. This reaction was investigated with thermal analysis under air and nitrogen atmosphere. By changing temperature and time parameters, the actual yield of conversion in question was examined analytically and the optimum temperature and time were found for the reaction. The rate expression of the solid phase reaction was also investigated and the rate equation was obtained.


Quantum-Chemical Investigations On The Functionalized 1h-Pyrimidines, İsmail Yildirim, Makbule Tezcan, Yahya Güzel, Emin Saripinar, Yunus Akçamur Jan 1996

Quantum-Chemical Investigations On The Functionalized 1h-Pyrimidines, İsmail Yildirim, Makbule Tezcan, Yahya Güzel, Emin Saripinar, Yunus Akçamur

Turkish Journal of Chemistry

Conformational analysis and quantum-chemical calculations were carried out by means of the methods MMP2 and SCF MO LCAO in the CNDO/2 and MNDO approximation for the series of compounds being functionalized 1H- pyrimidines. The analysis of the electron density distribution depending on the substituents' nature was done on the basis of the data obtained.


Poly (D,L-Lactic Acid) Homopolymers: Synthesis And Characterization, Xu Kaitian, Ahmet Kozluca, Emir B. Denkbaş, Erhan Pi̇şki̇n Jan 1996

Poly (D,L-Lactic Acid) Homopolymers: Synthesis And Characterization, Xu Kaitian, Ahmet Kozluca, Emir B. Denkbaş, Erhan Pi̇şki̇n

Turkish Journal of Chemistry

In this study, poly(D,L-lactic acid or D,L-lactide) (PDLLA) homopolymers were synthesized with different molecular weights. Low molecular weight PDLLAs (MW_n: 500-2300) were synthesized by direct polycondensation of DL-lactic acid without using any catalyst, while high molecular weight PDLLAs ( MW_n: 8x10^3-150x10^3) were produced by ring-opening polymerization of DL-lactide with stannous chloride as catalyst (initiator). Average molecular weights of PDLLAs were determined by end-group analysis, by viscosimetric measurements and by HPLC. PDLLA homopolymers were characterized by FTIR, NMR and DSC. In the production of PDLLAs by direct polymerization, molecular weights of the PDLLAs increased with the increase in the polymerization time …


A Kinetic Study Of Homogeneous Bulk Polymerization Of Ethyl Methacrylate Initiated By Benzoyl Peroxide And An N, N^{\Prime} -Dimethylaniline Redox Pair, Serap Şenel, Belma Işik-Yürüksoy, Olgun Güven Jan 1996

A Kinetic Study Of Homogeneous Bulk Polymerization Of Ethyl Methacrylate Initiated By Benzoyl Peroxide And An N, N^{\Prime} -Dimethylaniline Redox Pair, Serap Şenel, Belma Işik-Yürüksoy, Olgun Güven

Turkish Journal of Chemistry

The homogenous bulk polymerization of ethyl methacrylate (EMA) was studied using benzoyl peroxide (BPO) and an N,N^{\prime}-dimethylaniline (DMA) redox pair with the dilatometric method. The half-order dependence of the polymerization rate upon both the BPO and DMA concentrations was obtained. The overall activation energy of the polymerization was found to be between 32.3-55.3 kJ/mole for different initial molar ratios of the redox pair. A retaring effect was observed at lower polymerization temperatures for low concentrations of BPO. The formation of reddish colored polymers at higher DMA concentrations was explained by the adsorption of adduct formed between DMA radicals.


Validity Of A Linear Estimator For The Total \Pi-Electron Energy Of Alternant Hydrocarbons, Lemi Türker Jan 1996

Validity Of A Linear Estimator For The Total \Pi-Electron Energy Of Alternant Hydrocarbons, Lemi Türker

Turkish Journal of Chemistry

The validity of a linear topological estimator formula which possesses a slope k such that 0


The Concept Of Molecular Similarity And The Angle Of Total \Pi-Electron Energy, Lemi Türker Jan 1996

The Concept Of Molecular Similarity And The Angle Of Total \Pi-Electron Energy, Lemi Türker

Turkish Journal of Chemistry

The concept of molecular similarity is developed and a novel similarity index based on the cosine of the angle of total \Pi-electron energy is proposed to interrelate structural variations to operant properties of molecules isoconjugate with alternant hydrocarbons.


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.


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 Jan 1996

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 …


Polyelectrolytes In Immunology: Fundametals And Perspectives, Mehmet I. Mustafaev Jan 1996

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 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.


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 …


Molecular Structure Of 2'-Hydroxy-3'-Methoxy-5'-Allyl -4-Methylazobenzene, Veysel T. Yilmaz, Selami Şasmaz, İsmail E. Gümrükçüoğlu, R. Alan Howie Jan 1996

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 Jan 1996

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 Jan 1996

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 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 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.