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Full-Text Articles in Physical Sciences and Mathematics

^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid Jan 2004

^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid

Turkish Journal of Chemistry

The reaction of 2-[(2,3-dimethylphenyl)amino]benzoic acid (HL) with tri- and diorganotin(IV) chlorides yielded complexes of the type R_{3}SnL and R_{2}SnL_{2} (R = n-C_{4}H_{9}, C_{6}H_{5}, C_{6}H_{5}CH_{2}, n-C_{8}H_{17}). The compounds R_{2}SnClL were obtained by a redistribution reaction between R_{2}SnL_{2} and R_{2}SnCl_{2}. All the compounds were characterized by CHN analysis, infrared, multinuclear NMR, mass and Mössbauer spectroscopy. The possible mode of carboxylate group bonding in solid as well as in solution is proposed on the basis of infrared, Mössbauer and NMR (^{1}H, ^{13}C, ^{119}Sn) spectroscopy.


Synthesis And Characterization Of Cu(Ii) Complexes Of Two Ligands Derived From Malonyl Dichloride, Nevi̇n Karaböcek, Serdar Karaböcek, Hasan Mazlum, İsmai̇l Deği̇rmenci̇oğlu, Keri̇m Serbest Jan 2004

Synthesis And Characterization Of Cu(Ii) Complexes Of Two Ligands Derived From Malonyl Dichloride, Nevi̇n Karaböcek, Serdar Karaböcek, Hasan Mazlum, İsmai̇l Deği̇rmenci̇oğlu, Keri̇m Serbest

Turkish Journal of Chemistry

Two different mononucleating ligands incorporating N_{4} and N_{2}S_{2} donor units, 2-(1,3-benzothiazole-2-yl-methyl)-1,3-benzothiazole (L^{1}) and N,N'-bis-(2-amino-phenyl)-malonamide (H_{2}L^{2}) were synthesized by a new method from malonyl dichloride as starting material, and their mononuclear copper(II) complexes were prepared and characterized by elemental analyses, ^{1}H- and ^{13}C-NMR, IR, magnetic moments and mass spectral studies. Elemental analyses, and stochiometric and spectroscopic data of the metal complexes indicate that the metal ions are coordinated to the nitrogen and sulfur atoms and the data support the proposed structure of L^{1}, H_{2}L^{2} and their mononuclear copper(II) complexes. Moreover, the copper(II) complexes of L^{1} and H_{2}L^{2} have a 1:1 metal …


Synthesis And Antimicrobial Activity Of Some Pyridyl And Naphthyl Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole Derivatives, Khosrow Zamani, Khalil Faghihi, Taraneh Tofighi, Mohammad Reza Shariatzadeh Jan 2004

Synthesis And Antimicrobial Activity Of Some Pyridyl And Naphthyl Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole Derivatives, Khosrow Zamani, Khalil Faghihi, Taraneh Tofighi, Mohammad Reza Shariatzadeh

Turkish Journal of Chemistry

Synthesis of new 1,2,4-tri and 1,3,4-thiadiazoles, bearing isomeric pyridyl and 1-naphthyl is reported using 1,4-disubstituted thiosemicarbazides in alkaline and acidic media, respectively. The methylthio and benzylthio derivatives of the synthesized triazoles are also reported. All of the synthesized compounds were characterized by their FT-IR, ^{1}H-NMR and mass spectral data. The antibacterial studies of some of the synthesized compounds against S. aureus} and E. coli} as MIC values are reported. None of them have important antibacterial activities.


Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan Jan 2004

Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan

Turkish Journal of Chemistry

From the roots of Verbascum lasianthum Boiss. ex Bentham 4 catalpol derivatives, 6-O-(\alpha-L-rhamnopyranosyl)-catalpol (1), verbascoside A [= 6-O-(4''-O-trans-p-methoxycinnamoyl)-\alpha -L-rhamnopy- ranosylcatalpol] (2), pulverulentoside I [= 6-O-(3''-O-acetyl-2''-O-trans-p-methoxycinnamoyl)-\alpha -L-rham-nopyranosylcatalpol] (3), and buddlejoside A_{5} [= 6-O-(2''-O-acetyl-3''-O-trans-p-methoxycinnamoyl)-\alpha -L-rhamnopyranosylcatalpol] (4), as well as aucubin (5) and an aucubin derivative, unduloside III [= 6-O-(3''-O-trans-p-methoxycinnamoyl)- \alpha-L-rhamnopyranosylaucubin] (6), were isolated and characterized. The structure elucidation of the compounds was established on the basis of spectroscopic evidence. Buddlejoside A_{5} (4) was found for the first time in the genus Verbascum.


Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya Jan 2004

Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya

Turkish Journal of Chemistry

Chloride 18 (47%) and alcohol 21 (44%) were isolated from the reaction of alcohol 20 with SOCl_2. Cyclopropylcarbinyl -- cyclopropylcarbinyl rearrangement leads to chloride 22, which hydrolyses on separation to give alcohol 21. Chloride 18 results from cyclopropyl -- allylcarbinyl rearrangement, followed by a 1,2 -- aryl shift (sequential rearrangement). Syntheses of compounds 23 and 24 support the structures. The behaviour of 20 differs from that of exo isomer 14, probably due to the nature of the intermediates in these reactions.


3-Hydroxy Fatty Acids From The Flowers Of Hypericum Lysimachioides Var. Lysimachioides, Hasan Çeti̇n Özen, Mehmet Başhan, Zuhal Toker, Cumali̇ Keski̇n Jan 2004

3-Hydroxy Fatty Acids From The Flowers Of Hypericum Lysimachioides Var. Lysimachioides, Hasan Çeti̇n Özen, Mehmet Başhan, Zuhal Toker, Cumali̇ Keski̇n

Turkish Journal of Chemistry

Fatty acid methyl esters in the leaves and flowers of Hypericum lysimachioides var. lysimachioides (Guttiferae) were analyzed by gas chromatography and gas chromatography-mass spectrometry. The flowers of H. lysimachioides var. lysimachioides produced unusual 3-hydroxy fatty acids [3-hydroxy- tetradecanoic acid (3-OH-C14:0) and 3-hydroxy-octadecanoic acid (3-OH-C18:0)], along with other normal fatty acids. Major components were linolenic and palmitic acids for both leaves and flowers.


Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker Jan 2004

Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker

Turkish Journal of Chemistry

A sensitive and simple enrichment method using microorganisms as an adsorbent is described for the determination of trace manganese in alloys. Manganese was determined by flame atomic absorption spectrometry after preconcentration onto Amberlite XAD-4 loaded with Saccharomyces carlsbergensis. The optimum values of pH, amount of adsorbent, amount of microorganism, eluent type and volume of sample solution were determined for the quantitative recovery (>95%) of manganese. Results have been compared with those obtained without using microorganisms. Under optimum conditions, recoveries were 98 \pm 3% with microorganisms and 68 \pm 2% without microorganisms for manganese at a 95% confidence level. The …


Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-Pyridin-2-Yl-1h- Pyrazole-3-Carboxylic Acid, Ahmet Şener, Esvet Akbaş, M. Kasim Şener Jan 2004

Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-Pyridin-2-Yl-1h- Pyrazole-3-Carboxylic Acid, Ahmet Şener, Esvet Akbaş, M. Kasim Şener

Turkish Journal of Chemistry

The 1H-pyrazole-3-carboxylic acid 2, obtained from the furandione 1 and 2-hydrazinopyridine, was decarboxylated to give 4-benzoyl-5-phenyl-1-pyridin-2-yl-pyrazole derivative 3. Some ester 4 derivatives of 2 were prepared by the Fischer esterification reactions of 2 with various alcohols. Cyclocondensation reactions of 2 with phenyl hydrazine or hydrazine hydrate led to the formation of derivatives of pyrazolo[3,4-d]pyridazine 5 derivatives.


Chemically Crosslinked N-Vinyl-2-Pyrrolidone/2-Hydroxyethyl Methacrylate (Vp/Hema) Copolymer For The Controlled Release Of Cyclic Oligopeptide, Bashir Ahmad, Shumaila Bashir, Shams-Un Nisa, M. B. Huglin Jan 2004

Chemically Crosslinked N-Vinyl-2-Pyrrolidone/2-Hydroxyethyl Methacrylate (Vp/Hema) Copolymer For The Controlled Release Of Cyclic Oligopeptide, Bashir Ahmad, Shumaila Bashir, Shams-Un Nisa, M. B. Huglin

Turkish Journal of Chemistry

Crosslinked copolymers of various compositions of N-vinyl-2-pyrrolidone (VP) and 2-hydroxyethyl methacrylate (HEMA) were prepared chemically in the presence of a crosslinking agent. The swelling mechanism was non-Fickian with about 86% conversion of feed composition to crosslinked copolymer. The reactivity ratios r_1 = 0.045 and r_2 = 3.07 for VP and HEMA indicate that HEMA is more reactive than VP in the reaction. Hydrophilicity, hydrophobicity and monomer composition in the copolymer controlled the drug release from the hydrogels.


A Convenient Synthesis Of 3,6-Disubstituted-1,4-Dihydro-[1,2,4,5]Tetrazines And Preparation Of New Acetic Acid Derivatives Containing 5-Oxo-4-Phenylamino- 4,5-Dihydro-[1,2,4]Triazole, Ahmet Demi̇rbaş Jan 2004

A Convenient Synthesis Of 3,6-Disubstituted-1,4-Dihydro-[1,2,4,5]Tetrazines And Preparation Of New Acetic Acid Derivatives Containing 5-Oxo-4-Phenylamino- 4,5-Dihydro-[1,2,4]Triazole, Ahmet Demi̇rbaş

Turkish Journal of Chemistry

A series of compounds 8a-e, was synthesized by condensation of compounds 7a-e with ethyl bromoacetate. The treatment of compounds 8a-e with hydrazine hydrate afforded the corresponding hydrazide derivatives (9a-e). Subsequently, compounds 9a-e were converted to alkylidene hydrazides (10a-e). Moreover, upon heating in the presence of carboxylic acids, compounds 9a-e unexpectedly gave 1,4-dihydro-[1,2,4,5]tetrazine derivatives (11a-e).


The Kinetics Of The Photochemical Reaction Of Methylene Green With Methylamine And Ethylamine, Rehana Saeed, Fahim Uddin, Zahida Khalid Jan 2004

The Kinetics Of The Photochemical Reaction Of Methylene Green With Methylamine And Ethylamine, Rehana Saeed, Fahim Uddin, Zahida Khalid

Turkish Journal of Chemistry

The photochemical reduction of methylene green with methylamine and ethylamine in 50% aqueous isopropanol was studied. The photochemical reduction was carried out in a special type of optical processor associated with a deoxygenating system, a temperature controlling unit and a magnetic stirring system. A monochromatic light of 657 nm wavelength was used for irradiation of oxygen free reaction solutions in a double walled reaction cell. The transmitted light was measured and recorded in terms of electrical signals with the help of a calibrated galvanometer. Acidities of the solutions were measured with the help of a spectrophotometer based on the Hammet …


Synthesis, Magneto-Spectral And Thermal Characteristics Of Some 7-Coordinated Compounds Of Lanthanides(Iii) Chlorides With 4[(Furan-2-Ylmethylene)Amino]-1,5-Dimethyl-2-Phenyl Pyrazol-3-One And Isonicotinic Acid(3',4',5'-Trimethoxybenzylidene)Hydrazide, Ram K. Agarwal, Surendra Prasad, Neetu Goel Jan 2004

Synthesis, Magneto-Spectral And Thermal Characteristics Of Some 7-Coordinated Compounds Of Lanthanides(Iii) Chlorides With 4[(Furan-2-Ylmethylene)Amino]-1,5-Dimethyl-2-Phenyl Pyrazol-3-One And Isonicotinic Acid(3',4',5'-Trimethoxybenzylidene)Hydrazide, Ram K. Agarwal, Surendra Prasad, Neetu Goel

Turkish Journal of Chemistry

In the present work, we describe the isolation of some lanthanide(III) chlorides coordination compounds with 4[(furan-2-ylmethylene)amino]-1,5-dimethyl-2-phenyl pyrazol-3-one (FDPPO) and isonicotinic acid(3',4',5'-trimethoxybenzylidene)hydrazide (ITMBH) with the general composition [Ln(L)_2Cl_3] (Ln = La, Pr, Nd, Sm, Gd, Tb, Dy or Ho; L = FDPPO or ITMBH). All the isolated compounds were characterized through various physico-chemical studies. The coordinating ligands FDPPO or ITMBH act as neutral bidentate N and O-donors in the present compounds. The central metal ion displays the coordination number 7 in these complexes. Thermal stabilities of these complexes were also studied through thermogravimetric analysis.


Diffusion Effect On The Anodic Reactions Of Tungsten, Mustafa Anik, Tuba Cansizoğlu, Si̇nem Çevi̇k Jan 2004

Diffusion Effect On The Anodic Reactions Of Tungsten, Mustafa Anik, Tuba Cansizoğlu, Si̇nem Çevi̇k

Turkish Journal of Chemistry

Potentiodynamic and potentiostatic polarizations, and a rotating disk electrode technique were used to study the influence of diffusion on the anodic reactions of tungsten (W) in a broad pH range (\sim 0.3--13.5) in H_3PO_4 buffered solutions. The anodic current was controlled totally by the kinetics of H^+ -assisted dissolution below pH 1 (Region A). At around pH 2.5 (Region B), in addition to the kinetics of H_2O-assisted dissolution, specimen rotation had an effect on the current. This observation was attributed mainly to the physical damage to an oxide phase by hydrodynamic effects and partly to the diffusion of surface H_2WO_4(aq) …


Synthesis And Microbiological Activity Of Some Substituted N-(2-Hydroxy-4-Nitrophenyl)Benzamides And Phenylacetamides As Possible Metabolites Of Antimicrobial Active Benzoxazoles, İlkay Yildiz Ören, Esi̇n Aki Şener, Cengi̇z Ertaş, Özlem Temi̇z Arpaci, İsmai̇l Yalçin, Nurten Altanlar Jan 2004

Synthesis And Microbiological Activity Of Some Substituted N-(2-Hydroxy-4-Nitrophenyl)Benzamides And Phenylacetamides As Possible Metabolites Of Antimicrobial Active Benzoxazoles, İlkay Yildiz Ören, Esi̇n Aki Şener, Cengi̇z Ertaş, Özlem Temi̇z Arpaci, İsmai̇l Yalçin, Nurten Altanlar

Turkish Journal of Chemistry

Some new antimicrobial active N-(2-hydroxy-4-nitrophenyl)- p-substituted benzamide and phenylacetamide analogues (I-II) were prepared by 2-step procedures from the corresponding carboxylic acids as possible metabolites of benzoxazoles. Their antimicrobial activities were tested against 3 Gram-positive and 2 Gram-negative bacteria with the fungus Candida albicans and were also compared with several control drugs. The compounds Ia, Id, IIa, and IIe were active at a MIC value of 12.5 \mu g/mL against the Gram-positive microorganism Bacillus subtilis. Most of the compounds exhibited antifungal activity at a MIC value of 12.5 \mu g/mL against C. albicans. On the other hand, the antimicrobial activity of …


Synthesis And Antinociceptive Activity Of 2-[(2-Oxobenzothiazolin-3-Yl)Methyl]- 5-Aminoalkyl/Aryl-1,3,4-Thiadiazole, Ti̇jen Önkol, Bi̇lge Çakir, M. Fethi̇ Şahi̇n, Engi̇n Yildirim, Kevser Erol Jan 2004

Synthesis And Antinociceptive Activity Of 2-[(2-Oxobenzothiazolin-3-Yl)Methyl]- 5-Aminoalkyl/Aryl-1,3,4-Thiadiazole, Ti̇jen Önkol, Bi̇lge Çakir, M. Fethi̇ Şahi̇n, Engi̇n Yildirim, Kevser Erol

Turkish Journal of Chemistry

Ten 2-[(2-oxobenzothiazolin-3-yl)methyl]-5-aminoalkyl/aryl-1,3,4-thiadiazole derivatives were synthesized. The chemical structures of these compounds were elucidated by their FT-IR and ^1H-NMR spectral data, as well as their elemental analyses. The compounds were tested for antinociceptive activity. Among these compounds, 2-[(2-oxobenzothiazolin-3-yl)methyl]-5-aminomethyl-1,3,4-thiadiazole (5a) was found to be significantly more active than the others and the standards in all the tests.


The Hydrodynamic Properties Of Micelles Formed By Block Copolymers Of Isoprene And Tert-Butylacrylate In N-Octane, Hali̇l İbrahi̇m Ünal, Colin Price Jan 2004

The Hydrodynamic Properties Of Micelles Formed By Block Copolymers Of Isoprene And Tert-Butylacrylate In N-Octane, Hali̇l İbrahi̇m Ünal, Colin Price

Turkish Journal of Chemistry

The hydrodynamic properties of micelles formed by 2 block copolymers of isoprene and tert-butylacrylate in n-octane were investigated by dynamic light scattering (DLS) over a range of temperatures and concentrations using both the cumulants and histogram methods. By means of the histogram method it was possible to determine the average hydrodynamic diameters of both micelles and unassociated-chains in the same solution. It was also used to determine the z-average fraction of unassociated-chains at a particular concentration and temperature, and it provided an alternative route when combined with static light scattering (SLS) for determining the thermodynamics of micellisation. The overall-average diffusion …


Synthesis And Characterization Of Block Copolymers Using Polysiloxane Based Macroazoinitiator, Sennur Deni̇z, Ni̇l Baran, Mesut Akgün, Nalan A. Akgün, Sali̇h Di̇nçer Jan 2004

Synthesis And Characterization Of Block Copolymers Using Polysiloxane Based Macroazoinitiator, Sennur Deni̇z, Ni̇l Baran, Mesut Akgün, Nalan A. Akgün, Sali̇h Di̇nçer

Turkish Journal of Chemistry

Poly(dimethylsiloxane-b-styrene) (PDMS-b-PSt) and poly(dimethylsiloxane-b-methyl methacrylate) (PDMS-b-PMMA) block copolymers containing siloxane segments were studied by the radical polymerizations of vinyl monomers such as styrene (St) and methyl methacrylate (MMA) using polydimethylsiloxane based macroazoinitiator (PDM-MAI) in solution. PDM-MAI was synthesized by reacting hydroxy-terminated polydimethylsiloxane (PDMS) and 4,4'-azobis (4-cyanopentanoyl chloride) (ACPC) having a thermodegradable azo-linkage. The polycondensation reaction between PDMS and ACPC (2:1, molar ratio) was carried out at room temperature. The polymerizations of St and MMA initiated by PDM-MAI were investigated using different PDM-MAI concentrations (1, 5, 10, and 15 wt. %) for various reaction times with a methyl ethyl ketone (MEK)/ …


Studies On The Reactions Of 4-Ethoxycarbonyl-5-Phenyl-2,3-Dihydro-2,3- Furandione With Some Nh Nucleophiles, Ahmet Şener, Hasan Genç, İsrafi̇l Tozlu, M. Kasim Şener Jan 2004

Studies On The Reactions Of 4-Ethoxycarbonyl-5-Phenyl-2,3-Dihydro-2,3- Furandione With Some Nh Nucleophiles, Ahmet Şener, Hasan Genç, İsrafi̇l Tozlu, M. Kasim Şener

Turkish Journal of Chemistry

4-Ethoxycarbonyl-5-phenyl-2,3-dihydro-2,3-furandione 1 was reacted with o-phenylenediamine, substituted ureas and methylcarbamate or acetamide to give quinoxaline 2, pyrimidine 3 and benzoylmalonic acid 4 derivatives, respectively. Benzoylmalonic acid derivative 4a was converted into a new oxozinedione derivative, 5, by refluxing its solution in xylene containing a catalytic amount of p-toluene sulfonic acid. In addition, triphenylpyrazole carboxylic acid derivative 6 was obtained from the reaction of 4a with diphenylhydrazine.


The Crystal And Molecular Structure Of 1-(2-Chloro-Benzoyl)-3-P-Tolyl-Thiourea, Hakan Arslan, Ulrich Flörke, Nevzat Külcü Jan 2004

The Crystal And Molecular Structure Of 1-(2-Chloro-Benzoyl)-3-P-Tolyl-Thiourea, Hakan Arslan, Ulrich Flörke, Nevzat Külcü

Turkish Journal of Chemistry

1-(2-Chloro-benzoyl)-3-p-tolyl-thiourea was synthesized and characterized by elemental analysis and IR spectroscopy. The crystal and molecular structure of the title compound was determined from single-crystal X-ray diffraction data. It crystalizes in the triclinic space group P-1, with a = 7.9942(9) Å, b = 9.531(1) Å, c = 11.075(1) Å, \alpha = 97.235(2) °, \beta = 111.099(2) °, and \gamma = 106.105(2) °.


Secondary Metabolites From Phlomis Kotschyana, Ü. Şebnem Harput, İclal Saracoğlu, İhsan Çaliş, Ali̇ Arslan Dönmez, Akito Nagatsu Jan 2004

Secondary Metabolites From Phlomis Kotschyana, Ü. Şebnem Harput, İclal Saracoğlu, İhsan Çaliş, Ali̇ Arslan Dönmez, Akito Nagatsu

Turkish Journal of Chemistry

A lignan glycoside, syringaresinol-4',4''-O-di-\beta -D-glucopyranoside (1) (=liriodendrin), 4 phenylethanoid glycosides, acteoside (2), isoacteoside (3), forsythoside B (4) and leucosceptoside B (5), a caffeic acid ester, chlorogenic acid (6) and 2 iridoid glucosides, lamiide (7) and auroside (8), were isolated from the methanolic extracts of the aerial parts of Phlomis kotschyana along with an acetophenone glycoside, 4-hydroxyacetophenone 4-O-[6'-O-\beta -D-apiofuranosyl]-\beta -D-glucopyranoside (9). The structures of the isolated compounds were identified on the basis of spectroscopic (UV, IR, 1D- and 2D-NMR, and FAB-MS) methods.


Trace- And Rare-Earth Element Geochemistry Of The Karalar (Gazipaşa-Antalya) Barite-Galena Deposits, Southern Turkey, Gülcan Bozkaya, Ahmet Gökçe Jan 2004

Trace- And Rare-Earth Element Geochemistry Of The Karalar (Gazipaşa-Antalya) Barite-Galena Deposits, Southern Turkey, Gülcan Bozkaya, Ahmet Gökçe

Turkish Journal of Earth Sciences

The Karalar barite-galena deposits are typical examples of carbonate-hosted barite-galena deposits that occur widely in the central Taurides. Recent mining activity has been concentrated in the Büyük and Boyalık mine areas. The mineralisation occurs as ore veins along fault zones and as ore-filled breccia zones along the strongly deformed lower walls of limestone blocks in the Permian limestones of the Bıçkıcı Formation. These veins contain mainly barite (80-85%) and galena (10-15%), and lesser amounts of sphalerite, pyrite, fahlore, limonite, quartz and calcite as gangue minerals. Barite developed during an early episode of mineralisation and was mylonitised before the precipitation of …


Halitpaşa Transpressive Zone: Implications For An Early Pliocene Compressional Phase In Central Western Anatolia, Turkey, Orhan Kaya, Engi̇n Ünay, Gerçek Saraç, Silke Eichhorn, Sabine Hassenrück, Andrea Knappe, Asaf Pekdeğer, Serdar Mayda Jan 2004

Halitpaşa Transpressive Zone: Implications For An Early Pliocene Compressional Phase In Central Western Anatolia, Turkey, Orhan Kaya, Engi̇n Ünay, Gerçek Saraç, Silke Eichhorn, Sabine Hassenrück, Andrea Knappe, Asaf Pekdeğer, Serdar Mayda

Turkish Journal of Earth Sciences

The Late Cenozoic evolution of the eastern Aegean is dominated by widespread continental extension. The most prominent structures are E-W- and NE-SW-trending grabens and intervening horsts, while NW-SE- and N-S-trending faults form the other less important structures. This paper documents the results of recent geological mapping and structural and stratigraphical analysis from the Halitpaşa half graben, which forms the northwestern continuation of the Gediz Graben. Field evidence for a new NW-SE-trending dextral wrench-dominated fault zone (here named the Halitpaşa transpression zone), which involved the thrusting of pre-Palaeogene basement onto Upper Miocene-Lower Pliocene sediments, is presented. The fault zone is correlated …


Realizations Of The Osp(2,1) Superalgebra And Related Physical Systems, Hayri̇ye Tütüncüler, Ramazan Koç Jan 2004

Realizations Of The Osp(2,1) Superalgebra And Related Physical Systems, Hayri̇ye Tütüncüler, Ramazan Koç

Turkish Journal of Physics

Eigenvalues and eigenfunction of two-boson 2 \times 2 Hamiltonians in the framework of the superalgebra osp(2,1) are determined by presenting a similarity transformation. The Hamiltonians include two bosons and one fermion have been transformed in the form of the one variable differential equations and the conditions for its solvability have been discussed. It is observed that the Hamiltonians of the various physical systems can be written in terms of the generators of the osp(2,1) superalgebra and under some certain conditions their eigenstates can exactly be obtained. In particular, the procedure given here is useful in determining eigenstates of the Jaynes-Cummings …


Analysis Of One-Nucleon Transfer Cross-Sections, A. K. A. R. Al-Farra Jan 2004

Analysis Of One-Nucleon Transfer Cross-Sections, A. K. A. R. Al-Farra

Turkish Journal of Physics

The angular distributions of ^{26}Mg(^3H,^2H)^{27}Mg and ^{30}Si(^3H,^2H)^{31}Si reactions have been successfully studied using distorted wave Born approximation (DWBA) calculations. The optical model potentials are taken to have Woods-Saxon, parity and spin-orbit interactions. The present analysis gives a satisfactory fit to the forward angle data but grossly over estimates the cross-sections in the backward regions. The spin-orbit potential provides the best description of the experimental data and is found to be necessary to account for the large-angle cross sections. The obtained values of the extracted spectroscopic factors are reasonable.


Empirical Correlations Of Global Solar Radiation With Meteorological Data For Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk Jan 2004

Empirical Correlations Of Global Solar Radiation With Meteorological Data For Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk

Turkish Journal of Physics

Multiple linear regression models were developed to estimate the monthly average daily global solar radiation using ten parameters during a period of sixteen years (1984 to 1999) for Onne, Nigeria; the extraterrestrial radiation, average daily temperature, ratio of minimum and maximum daily temperature, relative humidity, ratio of sunshine duration, solar declination, average soil temperature, average pan evaporimeter, average rain fall and average daily dew. Even though up to ten variable correlations has been developed; the results showed that eight variable correlations with the highest value of correlation coefficient R gives the best result when considering the error terms (mean percentage …


Electrical Properties Of Hydrogen Transport Vpe Grown N-Cdte Epilayers On Znte/Gaas, Murat Bayhan Jan 2004

Electrical Properties Of Hydrogen Transport Vpe Grown N-Cdte Epilayers On Znte/Gaas, Murat Bayhan

Turkish Journal of Physics

Electrical characterisation of n-CdTe epilayers grown by hydrogen transport vapour phase epitaxy (H_2T-VPE) on insulating ZnTe/(100)GaAs substrates through the temperature dependent Hall measurements is reported. Double-crystal X-ray diffraction assessments indicate the material high crystalline quality. Samples grown at temperatures, T_G < 650 °C were p-type, but appeared to be n-type for the temperatures above T_G > 650 °C. Hall measurements performed on n-type samples of different thicknesses grown at T_G = 764 °C showed room temperature carrier densities in the range of 10^{11}-10^{14} cm^{-3}. The electron density and Hall mobility characteristics may be in principle well explained with a two-level affective model. The model of scattering by lattice and ionised impurity were found to be limiting …


Variation Of Chemical Potential Oscillations Of A 2deg In A Quantum Well Under A Magnetic Field For Multiple Sub-Band Occupation As Function Of Temperature And Level-Broadening, Berri̇n Özdemi̇r, Zeki̇ Yarar, Meti̇n Özdemi̇r Jan 2004

Variation Of Chemical Potential Oscillations Of A 2deg In A Quantum Well Under A Magnetic Field For Multiple Sub-Band Occupation As Function Of Temperature And Level-Broadening, Berri̇n Özdemi̇r, Zeki̇ Yarar, Meti̇n Özdemi̇r

Turkish Journal of Physics

We study the variation of chemical potential in a two dimensional electron gas in a uniform magnetic field as a function of temperature and level-broadening parameter. Schrödinger and Poisson equations are solved self-consistently for a two dimensional electron gas formed in a Ga_xAl_{1-x}As/GaAs quantum well, to numerically determine the potential profile, empty or occupied energy sub-bands, the wavefunctions and electron concentrations corresponding to each sub-band at various temperatures. Then assuming that the electron concentration is not altered, the variation of chemical potential with respect to both temperature and energy level-broadening parameter is studied under a uniform and constant magnetic field. …


Effect Of Iron Concentrations On Some Physical Properties Of The System Li_{0.5}Fe_{X}Ga_{2.5 - X}O_{4}, Abd El-Raouf Tawfik, N. Tashtoush, O.M. Hemeda Jan 2004

Effect Of Iron Concentrations On Some Physical Properties Of The System Li_{0.5}Fe_{X}Ga_{2.5 - X}O_{4}, Abd El-Raouf Tawfik, N. Tashtoush, O.M. Hemeda

Turkish Journal of Physics

A series of Li_{0.5} Fe_{x} Ga_{2.5 - x} O_{4} systems were prepared for x = 0, 0.25, 0.5, 0.75 and 1 by the general ceramic method. X-ray diffraction showed that all compositions have single phase Spinel cubic structure. The lattice parameter increased with enhancing iron concentration. The thermoelectric coefficient decreased with increasing x, and the majority carriers are holes. The increase of the jump length of hole increased the electrical conductivity. Jump-length increased with iron concentration and the rate of jumping gave rise to the electrical conductivity. The concentration of Fe^{3 +} ions in Lithium gallate is important, for such …


Quantum Statistical Entropy Of Sen Black Hole, Zhao Ren, Wu Yueqin, Zhang Lichun Jan 2004

Quantum Statistical Entropy Of Sen Black Hole, Zhao Ren, Wu Yueqin, Zhang Lichun

Turkish Journal of Physics

In this paper, by using quantum statistical methods, we directly obtain the partition function of Bose field and Fermi field on the background of the axisymmetrical Sen black hole. The difficult-to-solve wave equation is avoided. Then via the improved brick-wall method and membrane model, we calculate the entropy of Bose field and Fermi field of the black hole. We find that the entropy of the black hole is proportional to the area of the horizon. In our results, we do not encounter the left out term nor the divergent logarithmic term that appears in the original brick-wall method. The question …


E2/M1 Multipole Mixing Ratios Of Transitions In Erbium Isotopes, Harun Reşi̇t Yazar, İhsan Uluer Jan 2004

E2/M1 Multipole Mixing Ratios Of Transitions In Erbium Isotopes, Harun Reşi̇t Yazar, İhsan Uluer

Turkish Journal of Physics

Erbium isotopes (Z = 64) lie in the transitional region that occurs at the middle of the range of deformed nuclei. \gamma -ray E2/M1 mixing ratios for selected transitions in ^{166-168}Er are calculated in the proton-neutron interacting boson approximation(IBA-2). The results obtained for ^{166 -168}Er are reasonably in good agreement with the previous experimental and teoretical values.