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Articles 10171 - 10200 of 10230
Full-Text Articles in Physical Sciences and Mathematics
Catalysis Of Autoxidation Of 2,6-Di-Tert-Butylphenol In Water By Metallophthalocyanine Tetrasulfonates Bound To Polyelectrolyte Supports, Yasemin Tura Kopkalli, Hayrettin Türk
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.
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
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.
The Effects Of Polyacrylic Acid/Polypyrrole Composite Coating On Photocorrosion And Photoactivity Of Pyrite Electrodes, A. Sezai Saraç, Belkıs Ustamehmetoğlu, Esma Sezer, Candan Erbi̇l
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.
Validity Of A Linear Estimator For The Total \Pi-Electron Energy Of Alternant Hydrocarbons, Lemi Türker
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 Mechanism Of The Photoprotolytic Reactions Of Some Oxyazomethine Compounds, Lubov Efimovna Zelt'ser, Milan B. Bastic, Ljubinka V. Rajakovic
The Mechanism Of The Photoprotolytic Reactions Of Some Oxyazomethine Compounds, Lubov Efimovna Zelt'ser, Milan B. Bastic, Ljubinka V. Rajakovic
Turkish Journal of Chemistry
The kinetic spectral study of the photoprotolytic reactions of oxyazomethine molecules was performed. It was established that the deprotonation reactions of oxyazomethines proceed with the participation of electronically excited molecules and are characterized by parameters which differ to basic state reactions.
Distribution Of Ce (Iv) Species In Hno_{3}-Hcio_{4} Media And Determination Of Stability Constants Of The Nitrato Complexes, Seval Bayülken, A. Sezai Saraç
Distribution Of Ce (Iv) Species In Hno_{3}-Hcio_{4} Media And Determination Of Stability Constants Of The Nitrato Complexes, Seval Bayülken, A. Sezai Saraç
Turkish Journal of Chemistry
In this paper, the distribution of cerium (IV) species depending on the charges of nitric acid-perchloric acid concentration at constant ionic strength (I=1.0) was investigated. Cerium (IV), being a strong oxidant, was utilized for investigating the oxidation kinetics of some amino acids. Knowing the distribution of cerium (IV) species is beneficial for better understanding this type of kinetics. Distribution of cerium (IV) species in aqueous media was studied by measuring the total optical absorbance of cerium (IV) species in different nitric acid-perchloric acid mixture solutions. The stability constants (K_{1} and K_{2}) of the nitrato cerium complexes were determined spectrophotometrically from …
Automation Of Dipole Moment Measurements Using Microprocessor Controlled System, Nil Tarim, Hakan Kuntman, Ayten Kuntman
Automation Of Dipole Moment Measurements Using Microprocessor Controlled System, Nil Tarim, Hakan Kuntman, Ayten Kuntman
Turkish Journal of Chemistry
A microprocessor controlled instrument that can be used in physical chemistry research laboratories has been designed and constructed. The intended use is the measurement of the dipole moment and determination of the temperature dependency of the dipole moment for polar substances, especially for macromolecules. Measurement techniques with conventional dipolmeters require fine adjustments and measurements which seem to be very tedious and time consuming. Provided automation enables very frequent measurements with a step of 1^{\circ}C and disallows any user-oriented error. The dielectric constant measurement is performed within an accuracy limit of less than \pm 0.001. Furthermore, the equipment designed provides the …
Enantioselective Synthesis Of 4-Hydroxy-3-(3-Oxo-1-Phenyl Butyl)- 2h-1-Benzopyran-2-One (Warfarin), Ayhan S. Demi̇r, Cihangir Tanyeli, Volkan Gülbeyaz, Hülya Akgün
Enantioselective Synthesis Of 4-Hydroxy-3-(3-Oxo-1-Phenyl Butyl)- 2h-1-Benzopyran-2-One (Warfarin), Ayhan S. Demi̇r, Cihangir Tanyeli, Volkan Gülbeyaz, Hülya Akgün
Turkish Journal of Chemistry
Oral anticoagulant Warfarin (4-hydroxy-3-(3-oxo-1-phenyl butyl)-2H-1- benzopyran-2-one) is synthesized in optically active form starting from 4- hydroxycoumarin via formation of optically active enamines followed by Michael addition reaction with benzyliden acetone at low temperature. Different amines gave 17-68\% ee and the chemical yield was 22-71\%, depending on the reaction conditions and the structure of chiral amines.
Synthesis Of Some Pyrazolo-Pyridazine Compounds, Adem Önal, Yunus Akçamur, Behzat Altural
Synthesis Of Some Pyrazolo-Pyridazine Compounds, Adem Önal, Yunus Akçamur, Behzat Altural
Turkish Journal of Chemistry
Addition of {\bf 1} to two moles of phenylhydrazine gives 1,2,4,6- tetraphenyl-(2,3-d)-pyrazolo-5,6-pyridazine-7-one {\bf 4} isomer compound 1, 2,3,5-tetraphenyl-(2,3-d) pyrazolo-5,6-pyridazine-7-one {\bf 5} of {\bf 4} was synthesized by the reaction of {\bf 2} with phenylhydrazine. 3,4- Diphenyl-(2,3-d)-pyrazolo-(1H,6H)-pyridazine-7-one {\bf 6} was also obtained in two different ways. Reaction of {\bf 1} and 4-benzoyl-5 phenyl- furan-2,3-dione {\bf 3} with hydrazinium hydrate furnished compound {\bf 6}. The structures of {\bf 4,5} and {\bf 6} were determined by the ^{13} C- NMR, IR spectra and elemental analysis. These new isomer and condensed compounds synthesized in this study are important for heterocyclic chemistry.
A New Prodelphinine Type Alkaloid From, Ali H. Meri̇çli̇, Filiz Meri̇çli̇, Hans Becker, Ayhan Ulubelen
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.
Cycloaddition Reactions Of Dichloroketene To Allyl Ethers, Hülya Şenöz, Süleyman Yildirir
Cycloaddition Reactions Of Dichloroketene To Allyl Ethers, Hülya Şenöz, Süleyman Yildirir
Turkish Journal of Chemistry
Allyl ethers reacted with dichloroketene by [2+2] Cycloaddition to produce 2,2-dichlorocyclobutanones structure of products were determined by IR, NMR, GC MS tecniques.
Fixed Bed Pyrolysis And Hydropyrolysis Of An Immature Type I Turkish Oil Shale, Murat Çitiroğlu, Selma Türkay, Zeynep Işık Cepni̇, Colin Edward Snape
Fixed Bed Pyrolysis And Hydropyrolysis Of An Immature Type I Turkish Oil Shale, Murat Çitiroğlu, Selma Türkay, Zeynep Işık Cepni̇, Colin Edward Snape
Turkish Journal of Chemistry
A number of different pyrolysis procedures were investigated in order to achieve higher oil yields from an immature type I oil shale than obtained under static retorting conditions. Both nitrogen and steam gases increased yields as inticipated: Steam achieving comparable yields to nitrogen but at much lower gas velocities. The composition of the tars varied considerably, steam increasing the concentration of alkenes. In coprocessing the oil shale with a Turkish lignite in the Heinze retort, oil yields were higher than predicted principally due to extraction of the lignite by pyrobitumens obtained from the oil shale. Fixed bed hydropyrolysis of the …
Synthesis Of 2[1'(3',5'-Disubstituted Pyrazolyl) Methyl]5-Phenyl Amino-1,3,4-Thiadiazoles And 1,2,4-Triazoles As Potential Therapeutic Agents, Roshan Ahmad, M. Zia-Ul-Haq, Rukhsana Jabeen, Helmut Duddeck
Synthesis Of 2[1'(3',5'-Disubstituted Pyrazolyl) Methyl]5-Phenyl Amino-1,3,4-Thiadiazoles And 1,2,4-Triazoles As Potential Therapeutic Agents, Roshan Ahmad, M. Zia-Ul-Haq, Rukhsana Jabeen, Helmut Duddeck
Turkish Journal of Chemistry
A complete synthesis of 2[1'(3', 5'-disubstituted pyrazolyl) methyl] 5- phenyl-1,3,4-thiadiazole V(a-b) and 1,2,4-trizole VI (a-b) is reported. Cyclocondensation of \beta-diketones with etylhydrazino acetate hydrochloride yielded ethyl 3,5-disubstituted pyrazolyl acetate II(a-c) which on treatment with hydrazine hydrate resulted in the formation of their hydrazide derivatives III(a-c). These hydrazides, when treated with phenyl isothiocyanate, gave thiosemicarbazide derivatives IV(a-c), which were cyclised in the presence of con. H_{2}SO_{4} and NaOH to give V(a-b) and VI(a-b), respectively.
Extraction Of Dyestuff From Onion (Allium Cepa L.) And Its Application In The Dyeing Of Wool, Feathered-Leather And Cotton, Adem Önal
Turkish Journal of Chemistry
In this study, the total amount of dyeing substances present in onion (Allium cepa L.) was determined by using the extraction method. The extracted substanc were used in the dyeing of woollen strips, feathered- leather and cotton. Dyeing conditions and other characteristics were determined and the repeatable specifics were evaluated for these processes so that ligh fast colours could be obtained.
Synthesis Of Optically Active Camphorsulphonylbenzimidazoles, Mashooda Hasan, Humaira Masood, Naeema Khan, M. Zia-Ul-Haq
Synthesis Of Optically Active Camphorsulphonylbenzimidazoles, Mashooda Hasan, Humaira Masood, Naeema Khan, M. Zia-Ul-Haq
Turkish Journal of Chemistry
The preparation of optically active camphorsulphonylbenzimidazole {(\bf 1)}, a mixture of regioisomeric 5-nitro- {\bf (2A)} and 6-nitro-{\bf (2B)} camphorsulphonylbenzimidazoles, 5-nitro-{\bf (3A)} and 6-nitro-{\bf (3B)} 2- methyl camphorsulphonylbenzimidazoles is described. In this study the structure of the purified camphorsulphonylbenzimidazoles {\bf 1, 2B, 3A} and {\bf 3B} was confirmed by their mass and ^{1}H NMR spectral analysis. The specific rotation of each pure compound is also reported.
A Comparison Of Adsorption Isotherms Of Crosslinked Poly(N-Vinylpyrrolidone)/Basic Brown 1 Binding System, Dursun Saraydin, Erdener Karadağ
A Comparison Of Adsorption Isotherms Of Crosslinked Poly(N-Vinylpyrrolidone)/Basic Brown 1 Binding System, Dursun Saraydin, Erdener Karadağ
Turkish Journal of Chemistry
In this study, the binding of a basic dye such as basic brown 1 [BB 1] onto a crosslinked poly(N-vinylpyrrolidone) [CPVP] was investigated. Adsorption of the azo dye onto the CPVP was studied by the batch adsorption technique at 25^{\circ}C. In adsorption experiments a Langmuir type (L) adsorption was found with respect to the Giles classification system. Binding parameters such as initial binding constant (K_{i}), equilibrium constant {\it (K)}, monolayer coverage (n), site-size (u), and maximum fractional occupancy (\hat{\theta}), and thermodynamic parameters such as heat of adsorption (\Delta H), free energy of adsorption (\Delta G) and entropy of adsorption (\Delta …
The Facile Synthesis Of Cyclopentanoid Antibiotic Kjellmanianone, Ayhan S. Demi̇r, Cihangir Tanyeli̇, Volkan Gülbeyaz, Hülya Akgül
The Facile Synthesis Of Cyclopentanoid Antibiotic Kjellmanianone, Ayhan S. Demi̇r, Cihangir Tanyeli̇, Volkan Gülbeyaz, Hülya Akgül
Turkish Journal of Chemistry
The synthesis of cyclopentanoid antibiotic Kjellmanianone is described in this study. The C-acylation of lithium enolates of 3-Methoxycyclopentenone by N-carbomethoxyimidazole or methylcyanoformate \beta-ketoester, which when oxidized with Mn(III) acetate produces kjellmanianone in good yield.
Oxidative Coupling Of Methane On Lnba_{2}Cu_{3}O_{7-X} Superconductors, N. T. Shamilov, V. P. Vislovskii, E. A. Mamedov, S. M. Aliyev, A. I. Suleimanov, E. G. Ismailov
Oxidative Coupling Of Methane On Lnba_{2}Cu_{3}O_{7-X} Superconductors, N. T. Shamilov, V. P. Vislovskii, E. A. Mamedov, S. M. Aliyev, A. I. Suleimanov, E. G. Ismailov
Turkish Journal of Chemistry
The superconducting oxides LnBa_{2}Cu_{3}O_{7-x} (Ln=Y, Gd, Er, Yb, Lu) showed poor selectivity in the oxidative coupling of methane. The addition of 0.5 mol. %Li_{2}O to these materials considerably enhanced the yield of C_{2} hydrocarbons. This effect was related to both lower redox property and higher basicity of Li-doped catalysts as compared to those of undoped ones.
An Amperometric Biosensor For The Determination Of Organophosphorus Pesticides, Azmi Telefoncu
An Amperometric Biosensor For The Determination Of Organophosphorus Pesticides, Azmi Telefoncu
Turkish Journal of Chemistry
Organophosphorus pesticides are inhibitors of cholinesterase and this enzyme is used as a monitoring system for pesticides containing organophosphorus compounds. The decrease in activity of cholinesterase is monitored by the choline sensor and is correlated to the concentration of pesticide present in solution. According to this observation a biosensor for pesticides was determined. This biosensor consists of a Clark oxygen electrode, modified with cellulose acetate and dialysis membranes. Between the two membranes there are two immobilized enzymes: acetyl-cholinesterase and choline oxidase.
A New Flavanone From Teucrium Alyssifolium, G. Topcu, C. Eris, S. Kurucu A. Ulubelen
A New Flavanone From Teucrium Alyssifolium, G. Topcu, C. Eris, S. Kurucu A. Ulubelen
Turkish Journal of Chemistry
From the aerial parts of {\it Teucrium alyssifolium} in addition to previously obtained {\it neo-}clerodane diterpenoids, a new flavanone alysifolinone and three flavones cirsiliol, cirsilineol and luteolin-6,7,3', 4'-tetramethyl ether, were isolated. The structure of the compounds was established by spectral data, and by TLC comparison for the known compounds. Keywords: Teucrium alyssifolium, Lamiaceae, flavanone, alysifolinone, flovones.
A Comparison Of Normal(-Cn) And Reversed (C-18) Phase Chromatographic Behaviour Of Polycyclic Aromatic Hydrocarbons, S. Fatma Aygün, Mustafa Özci̇mder
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, water solubility and number of carbon atoms.
Adsorption Of Monovalent Cationic Dyes On Some Silicates, Oğuz İnel, Ayşegül Aşkin (Börekçi̇)
Adsorption Of Monovalent Cationic Dyes On Some Silicates, Oğuz İnel, Ayşegül Aşkin (Börekçi̇)
Turkish Journal of Chemistry
Adsorption of two cationic dyes, methylene blue (MB) and malachite green (MG), was studied on the bentonite, sepiolite and zeolite samples by the batch equilibration technique using a spectrophotometer. In addition, cation exchange capacities (CEC) of samples were determined by NH_4^{+} saturation using Kjeldhal distillation. The adsorption data was found to conform with the Langmuir equation within the concentration range studied, and Langmuir constants were determined for each of the samples. It was observed that the amount of dyes adsorbed was in excess of CEC in the case of bentonite and sepiolite. The adsorption capacities of the samples for both …
Investigation Of Adsorption Isotherms Used For Wool Dyeing By Aqueous Extraction Of Cehri Fruit (Fructus Rhamni Petiolari) And Dyeing Of Wool And Silk Accompanied By Various Mordants, A. Haluk Aydin, Fuat Güzel, Zeki Tez
Investigation Of Adsorption Isotherms Used For Wool Dyeing By Aqueous Extraction Of Cehri Fruit (Fructus Rhamni Petiolari) And Dyeing Of Wool And Silk Accompanied By Various Mordants, A. Haluk Aydin, Fuat Güzel, Zeki Tez
Turkish Journal of Chemistry
In this study, adsorption isotherms were obtained by processing wool with dyestuff solutions of different concentrations extracted from cehri fruit with water. These isotherms follow the Nernst equation; the Nernst constant was determined and interpreted. In addition, wool and silk fibres were dyed with the same dyestuff solution and various mordants. Colours having a high fastness which could be used on an industrial scale were produced.
Synthesis Of 2,4-Dihydro-4-(2-Phenylethyl)-5-(Isomeric Pyridyl)-3h-1,2,4-Triazole-3-Thiones And Their Derivatives., Rashid Iqbal, Khosrow Zamani, Nasim H. Rama
Synthesis Of 2,4-Dihydro-4-(2-Phenylethyl)-5-(Isomeric Pyridyl)-3h-1,2,4-Triazole-3-Thiones And Their Derivatives., Rashid Iqbal, Khosrow Zamani, Nasim H. Rama
Turkish Journal of Chemistry
Intramolecular cyclization of the three isomeric 1,4-disubstituted thiosemicarbazides 3(a-c) in aqueous sodium hydroxide was attempted to obtain 2,4-dihydro-4-(2-phenylethyl)-5-(isomeric pyridyl)- 3H-1,2,4-triazole-3-thiones 4(a-c). Each of the three isolated triazoles was separately treated with benzyl chloride and with chloroacetic acid to furnish the corresponding benzylthio 5(a-c) and carboxymethylthio derivatives 6(a-c), respectively
Synthesis, Characterization And Formation Kinetics Of Sn(Ii) And (Iv)-Schiff Base Complexes, Yakup Baran, Birgül Erk
Synthesis, Characterization And Formation Kinetics Of Sn(Ii) And (Iv)-Schiff Base Complexes, Yakup Baran, Birgül Erk
Turkish Journal of Chemistry
The synthesis and characterization of Sn(II) and Sn(IV) complexes of nitrogen and oxygen ligands, {\it p}-dimethyl aminophenylenesalicyladimine ( DPS), N,N'phenylenebis(salicylaldimine)(PBS) and N, N'-triethylenetetramine bis (salicylaldimine)(TTS) are reported. The structure of free ligands and their tin complexes were determined by elemental analysis, ir and nmr measurements. The kinetics of formation of the complexes were studied by stopped-flow technique at several temperatures with \mu=0.100 M (NaClO_{ 4}). Activation parameters \Delta H^{\ast} and \Delta S^{\ast} were determined.
The Sterols Of Cyclamen Coum, Nurettin Yayli, Cemalettin Baltaci
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).
An Unusual Zinc-Promoted Reductive Retro-Wagner-Meerwein Rearrangement, Yavuz Taşkesenli̇gi̇l, Metin Balci
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.
A Novel And Stereospecific Synthesis Of Conduritol-E Via Cyclohexa-3,5-Diene-1,2-Diol, Ahmet Maras, Hasan Secen, Yasar Sütbeyaz, Metin Balci
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
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 …
Study Of Interaction And Solubility Parameters Of Alkyl Methacrylate Polymers By Inverse Gas Chromatography, İsmet Kaya, Eyüp Özdemi̇r, Mehmet Coşkun
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.