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Studies On The Preparation Of \Alpha,\Omega -Telechelic Polymers By The Combination Of Reverse Atom Transfer Radical Polymerization And Atom Transfer Radical Coupling Processes, Bi̇nnur Aydoğan, Yusuf Yağci Jan 2007

Studies On The Preparation Of \Alpha,\Omega -Telechelic Polymers By The Combination Of Reverse Atom Transfer Radical Polymerization And Atom Transfer Radical Coupling Processes, Bi̇nnur Aydoğan, Yusuf Yağci

Turkish Journal of Chemistry

Monofunctional polystyrenes with cyano, carboxylic acid, and hydroxyl terminal groups were synthesized by reverse atom transfer radical polymerization (RATRP) using corresponding azo initiators in conjunction with copper and iron complexes. These functional polymers were further used in the atom transfer radical coupling (ATRC) reaction in the presence of Cu(I) and Cu(0) in order to obtain telechelic polystyrenes. In the iron-mediated system, while RATRP experiments gave satisfactory results, the corresponding ATRC process yielded polymers with low functionality. The copper-mediated system, however, gave contrary results. In the RATRP step, initiation efficiency was rather low and polymers with relatively higher polydispersity were obtained. …


Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao Jan 2007

Plasma-Initiated Polymerization Of (2-Methacryloyloxyethyl) Thrimethyl Ammonium Chloride, Yangang He, Gang Li, Jing Miao, Xueqing Yu, Fang Yang, Yingjun Cui, Fengxia Ren, Yang Chao

Turkish Journal of Chemistry

Plasma-initiated polymerization of (2-methacryloyloxyethyl) thrimethyl ammonium chloride (MTAC)) was studied. The effects of discharge time and discharge power on temperature in a tubular-type reactor chamber were accurately tested by on-line thermocouple, and the equation relating discharge time, discharge power and temperature in the tubular-type reactor chamber was derived. The results indicated that temperature played a very important role in controlling the solubility of Poly(MTAC) in water. For T \ge 130°, Poly(MTAC) was cross-linked, and the highest rate of absorbing water of Poly(MTAC) was 15 g · g^{-1}. For T < 130°, Poly(MTAC) was linear, and the highest intrinsic viscosity of Poly(MTAC) was 420.2 cm^3 · g^{-1}. The polymerization condition of linear Poly(MTAC) was optimized as follows: discharge time 60 s and discharge power 60 W.


Electrochemical Characteristics Of A 7-Ferrocenyl(Carbonyloxy)-1- Heptanethiol-Modified Gold Electrode, Mohammed Muzibur Rahman, Il Cheol Jeon Jan 2007

Electrochemical Characteristics Of A 7-Ferrocenyl(Carbonyloxy)-1- Heptanethiol-Modified Gold Electrode, Mohammed Muzibur Rahman, Il Cheol Jeon

Turkish Journal of Chemistry

The electrochemical properties of 7-ferrocenyl(carbonyloxy)-1-heptanethiol [FcCO_2(CH_2)_7SH] were characterized by an electrochemical quartz crystal microbalance (EQCM). A gold surface was modified with FcCO_2(CH_2)_7SH by the self-assembly method. EQCM was used to investigate mass change during the redox reactions of FcCO_2(CH_2)_7SH monolayers on a modified gold electrode in solution containing K_3Fe(CN)_6 redox species. The FcCO_2(CH_2)_7SH monolayer on gold acts as a mediator for the electron transfer between a gold electrode and electroactive species Fe(CN)_6^{3-/4-} in solution. In both cases, electrochemical current responses were complicated because the observed currents were due to the redox of both the ferrocenyl group immobilized on gold and …


Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari Jan 2007

Electron Affinities, Solvation Energies And Redox Potentials Of Some Chalcones: Substituents` Effect And Correlation With Semi-Empirical Mo Energies, Abdur Rahman, Rumana Qureshi, Mehvish Kiran, Farzana Latif Ansari

Turkish Journal of Chemistry

Experimental and theoretical investigations were carried out on 2 sets of chalcones. Set 1 has an OH group on ring A and Set 2 does not, and both have different substituents on ring B at different positions. The experimental investigations comprised cyclic voltammetric (CV) studies to determine the reactivity in terms of redox potentials in DMF at room temperature (23 \pm 1 °C). Electrochemical parameters from cyclic voltammograms were used to evaluate the reversibility of electron transfer, standard reduction potentials, solvation energies, electron affinities, diffusion coefficients, critical scan rates and heterogeneous electron transfer rate constants. Heterogeneous electron transfer rate constants …


A New And Convenient Method Of Generating Alkyl Isocyanates From Alcohols, Thiols, And Trimethylsilyl Ethers Using A 2,4,6-Trichloro[1,3,5] Triazine/N-Bu_4nocn, Batool Akhlaghinia, Sima Samiei Jan 2007

A New And Convenient Method Of Generating Alkyl Isocyanates From Alcohols, Thiols, And Trimethylsilyl Ethers Using A 2,4,6-Trichloro[1,3,5] Triazine/N-Bu_4nocn, Batool Akhlaghinia, Sima Samiei

Turkish Journal of Chemistry

Alkyl isocyanates are prepared in good to excellent yields by treatment of alcohols, thiols, and trimethylsilyl ethers with 2,4,6-trichloro[1,3,5] triazine/n-Bu_4NOCN in acetonitrile. This method is highly selective for conversion of 1° alcohols to alkyl isocyanates in the presence of 2° and 3° alcohols, thiols, and trimethylsilyl ethers.


Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu Jan 2007

Synthesis And Spectral Characterisation Of Chloro Organotin(Iv) Di[3(2`-Hydroxyphenyl)-5-(4-Substituted Phenyl) Pyrazolinates], Umesh Nath Tripathi, Mohammad Safi Ahmad, Goriparthi Venubabu

Turkish Journal of Chemistry

Chloro organotin(IV) dipyrazolinates of the type RSnCl(C_{15}H_{12}N_2OX)_2 [where C_{15}H_{12}N_2OX = 3(2'-Hydroxyphenyl)-5(4-X-phenyl)pyrazoline {where X = H (a); CH_3 (b); OCH_3 (c); Cl (d) and R = Me, Pr^n and Ph] were synthesised by the reaction of RSnCl_3 with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesised derivatives were characterised by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement and spectral [IR and multinuclear NMR (^1H, ^{13}C and ^{119}Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, ^1H and ^{13}C NMR spectral data. An octahedral structure around the tin(IV) …


Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu Jan 2007

Synthesis And Characterization Of Oligo-2-[(2-Hydroxymethylphenylimino) Methyl] Phenol And Oligo-2-[(2-Hydroxymethylphenylimino) Methyl]-5-Bromo-Phenol, İsmet Kaya, Ayşe Erçağ, Süleyman Çulhaoğlu

Turkish Journal of Chemistry

Oligo-2-[(2-hydroxymethylphenylimino) methyl] phenol O-(2-HMPIMP) and oligo-2-[(2-hydroxymet\-hylphenyl imino) methyl]-5-bromo-phenol O-(2-HMPIMBP) were synthesized by the oxidative polycondensation reaction using air as an oxidant in an aqueous alkaline medium at 70 °C. They were characterized by ^1H-NMR, FT-IR, UV-vis, TG, size exclusion chromatography (SEC) and elemental analysis. According to the SEC analyses, the number-average molecular weight (M_n), weight-average molecular weight (M_w) and polydispersity index (PDI) values of O-2-HMPIMBP and O-2-HMPIMP are 1100, 1600 g mol^{-1} and 1.45; and 6000, 6250 g mol^{-1} and 1.04, respectively. According to TG analyses, the weight losses of O-2-HMPIMP and O-2-HMPIMBP are 98.31% and 96.91%, respectively, at 900 …


New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi Jan 2007

New Aromatic Polyamide With Azo And Phosphine Oxide Groups In The Main Chain, Khalil Faghihi, Mohsen Hagibeygi

Turkish Journal of Chemistry

A new flame-retardant polyamide containing phosphine oxide and azobenzene moieties in the main chain was synthesized by the solution polycondensation reaction of 4,4`-azodibenzoic acid with bis(3-aminophenyl) phenyl phosphine oxide using thionyl chloride, N-methyl-2-pyrrolidone and pyridine. This new polymer was obtained in high yield (96%) and showed high inherent viscosity (0.55 dL/g) and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG) and solubility test. Furthermore, another polyamide was prepared by solution polycondensation reaction of 4,4`-azodibenzoic acid with 1,4-phenylene diamine and its flame-retardant behavior was compared by the use of the LOI with the previous one.


Preparation And Characterization Of An Atenolol Selective Electrode Based On A Pvc Matrix Membrane, Nabil S. Nassory, Shabaz A. Maki, Mutaz A. Ali Jan 2007

Preparation And Characterization Of An Atenolol Selective Electrode Based On A Pvc Matrix Membrane, Nabil S. Nassory, Shabaz A. Maki, Mutaz A. Ali

Turkish Journal of Chemistry

Atenolol selective electrodes were prepared based on a complex atenolol-phosphotungstate as an active material using the plasticizers di-butyl phosphate (DBP), tri-butyl phosphate (TBP), o-nitro phenyl octyl ether (NPOE) and di-octyl phthalate (DOPH) in a PVC matrix membrane. The properties of the prepared electrodes were studied, namely slope, concentration range, detection limit, lifetime, pH effect and selectivity. The experimental results showed that the best electrode was based on DOPH as plasticizer, displaying a linear range from 1.00 x 10^{-4} M to 5.00 x 10^{-2} M with a Nernstian slope of 55.91 mV/decade and correlation coefficient of 0.9995. The detection limit was …


Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi Jan 2007

Efficient Method For Tetrahydropyranylation Of Phenols And Alcohols Using 2,4,6-Trichloro[1,3,5]Triazine, Batool Akhlaghinia, Elham Roohi

Turkish Journal of Chemistry

Alcohols and phenols were tetrahydropyranylated in the presence of 2,4,6-trichloro[1,3,5]triazine in good to excellent yields in acetonitrile.


A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami Jan 2007

A Convenient Method For The Preparation Of 2-Aminobenzophenone Derivatives Under Ultrasonic Irradiation, Javad Safaei-Ghomi, Manouchehr Fadaeian, Alireza Hatami

Turkish Journal of Chemistry

A quick and convenient method for the preparation of 2-aminobenzophenone derivatives is described. This approach consists of the nucleophilic substitution reaction of nitrobenzenes by phenylacetonitrile under conventional and ultrasonic conditions followed by reduction of the produced 2,1-benzisoxazole to 2-aminobenzophenone. This 2-step reaction was studied by changing the reaction parameters (reaction temperature, ultrasound power, and reaction time). The results clearly demonstrated that using ultrasound irradiation results in a high yield within a short reaction time.


Gold(Iii) Complex Of Caffeine: Synthesis, Isolation And Spectroscopic Characterization, Bojidarka Ivanova Jan 2007

Gold(Iii) Complex Of Caffeine: Synthesis, Isolation And Spectroscopic Characterization, Bojidarka Ivanova

Turkish Journal of Chemistry

Au(III)-caffeine complex was synthesized and characterized by means of solid-state linear-dichroic infrared spectral analysis (IRLD), ^1H-NMR, MS, DSC and TGA methods. The caffeine (I) is monodentate and coordinated with metal ion through its N9 atom at molar ratio metal to ligand 1:1. The other 3 positions in the Au(III) coordination sphere are occupied by Cl^-, thus forming [Au^{3+}(C_8H_{10}N_4O_2)Cl_3] complex. IR-characteristic band assignment in the 4000-400 cm^{-1} IR region of pure ligand and corresponding Au(III)complex was performed.


Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin Jan 2007

Examination Of Gold As A Metal Promoter Of Sulphated Zirconia In N-Heptane Isomerisation At Low Temperature, Ümi̇t Bi̇lge Demi̇rci̇, Francois Garin

Turkish Journal of Chemistry

Isomerisation of nC_7 over a sulphated zirconia (SZ)-based bifunctional catalyst was studied at 150 °C. Au, Ir, Pd and Pt were used as promoters of SZ. The first objective was the production of C_7 isomers with high octane numbers. PtSZ is the most suitable catalyst despite low conversions and a high proportion of methylhexanes instead of dimethylpentanes. The second objective was to assess Au as a promoter of SZ. Au shows slight hydrogenation abilities, displaying behaviour similar to that of Pd, but is inactive towards alkane activation. These promising but inadequate results suggested that Au could be used as the …


Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.


Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Role Of Sn In The Density Of Defect States In A-Se_{0.75}Te_{0.25} And A-Se_{0.85}Te_{0.15}Thin Films, N. Sharma, Santosh Kumar Jan 2007

Role Of Sn In The Density Of Defect States In A-Se_{0.75}Te_{0.25} And A-Se_{0.85}Te_{0.15}Thin Films, N. Sharma, Santosh Kumar

Turkish Journal of Physics

In this paper we report the effect of Sn incorporation in the density of defect states of two binary Se-Te glassy systems, comparing the properties of a-Se_{0.75}Te_{0.25}, a-Se_{0.85}Te_{0.15} and a-Se_{0.75}Te_{0.15}Sn_{0.10} glassy alloys. Properties of d.c. conductivity at high electric fields in vacuum were examined; and current-voltage (I-V) characteristics have been measured at various fixed temperatures. Ohmic behavior is observed at low electric fields; while at high electric fields (E \sim 10^4 V/cm), non-ohmic behavior is observed. An analysis of the experimental data confirms the presence of space charge limited conduction (SCLC) in the studied glassy materials. Density of defect states …


2d Maxy--Jres Nmr Spectroscopy Of Ch_Nch_M (Ca_Ncx_M) Groups: Product Operator Theory And Simulation, İrfan Şaka, Sedat Gümüş, Azmi̇ Gençten Jan 2007

2d Maxy--Jres Nmr Spectroscopy Of Ch_Nch_M (Ca_Ncx_M) Groups: Product Operator Theory And Simulation, İrfan Şaka, Sedat Gümüş, Azmi̇ Gençten

Turkish Journal of Physics

There exist a variety of multi-pulse NMR experiments for spectral editing of complex molecules in solution. Maximum quantum correlation NMR spectroscopy (MAXY NMR) is one of the techniques for distinguishing CH_n groups by editing ^1H NMR spectra. Spectral assignments of 2D homonuclear J-resolved NMR spectroscopy become too difficult, due to complex overlapping spectra. In order to overcome this problem a new technique called 2D MAXY-JRES NMR spectroscopy, which is the combination of MAXY NMR and homonuclear J-resolved NMR spectroscopy techniques, is used. In this study, product operator theory of 2D MAXY-JRES NMR spectroscopy is performed for IS_n I'S'_m (I = …


A Combinatorial Approach Of Real Ga & Fuzzy To Atc Enhancement, Hossein Farahmand, Masoud Rashidinejad, Ali Akbar Gharaveici Jan 2007

A Combinatorial Approach Of Real Ga & Fuzzy To Atc Enhancement, Hossein Farahmand, Masoud Rashidinejad, Ali Akbar Gharaveici

Turkish Journal of Electrical Engineering and Computer Sciences

Under new de-regulated environment an open access to transmission system seems to be desired. Transmission system operators (TSOs) are encouraged to use the existing facilities more efficiently. This paper focuses on study of the best location for SVC as a FACTS device to improve voltage profile as well as maximum available transfer capacity (ATC) in order to achieve lower prices. Real genetic algorithm (RGA) is used for optimization technique and analytical hierarchy process (AHP) associated with fuzzy sets to obtain priority vector for each alternative to evaluate the GA fitness. The effectiveness of the proposed methodology is shown through case …


Modelling A Deposition Process In Collective Construction, Robert L. Stewart, R. Andrew Russell, Lindsay Kleeman Jan 2007

Modelling A Deposition Process In Collective Construction, Robert L. Stewart, R. Andrew Russell, Lindsay Kleeman

Turkish Journal of Electrical Engineering and Computer Sciences

During collective construction tasks, swarm robots coordinate their actions in space and time to build structures that conform to some given design or specification. In this paper, a simulation model and a mathematical model (based on a Markov chain) are introduced to describe the deposition process of a previously detailed robotic swarm system that uses templates and feedback to facilitate construction. The models are based on the behaviour and geometry of real robots and predict the dynamics observed during practical trials as well as explaining the occurrence of different spatial patterns of building blocks. Furthermore, the models provide an insight …


Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Swarms In Biology And Engineering, Kevin M. Passino Jan 2007

Swarms In Biology And Engineering, Kevin M. Passino

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.


Different Modes Of Stress Transfer In A Strike-Slip Fault Zone: An Example From The North Anatolian Fault System In Turkey, Osman Bektaş, Yener Eyüboğlu, Nafi̇z Maden Jan 2007

Different Modes Of Stress Transfer In A Strike-Slip Fault Zone: An Example From The North Anatolian Fault System In Turkey, Osman Bektaş, Yener Eyüboğlu, Nafi̇z Maden

Turkish Journal of Earth Sciences

The dextral North Anatolian Fault System (NAFS) extends for well over 1000 km from the compressive tectonic domain of eastern Anatolia into the broad and diverse tectonic domain of the western Anatolian, Marmara and Aegean regions. These different tectonic regimes are characterized by a narrow deformation zone in the east and a much broader deformation zone with multiple sub-parallel fault zones in the west. The spatial and temporal distribution of large historical and modern earthquakes (Mw>5) shows two distinctive macro-seismic zones in the eastern and western parts of the NAFS. The eastern macro-seismic zone, between the towns of Erzincan …


Constraints On The Origin Of The Balıkesir Thermal Waters (Turkey) From Stable Isotope (\Delta^{18}O, \Deltad, \Delta^{13}C, \Delta^{34}S) And Major-Trace Element Compositions, Hali̇m Mutlu Jan 2007

Constraints On The Origin Of The Balıkesir Thermal Waters (Turkey) From Stable Isotope (\Delta^{18}O, \Deltad, \Delta^{13}C, \Delta^{34}S) And Major-Trace Element Compositions, Hali̇m Mutlu

Turkish Journal of Earth Sciences

The Balıkesir thermal waters in northwestern Turkey have discharge temperatures in the range of 31.8-98.5 ºC, near neutral pH values of 6.40 to 8.40 and TDS contents between 327 and 2578 mg/l. Samples display variable chemical compositions changing from high-temperature Na_2SO_4-NaHCO_3 waters to warmer CaHCO_3 waters. Trace element concentrations of the waters show significant variation. Comparison between the concentrations of alkaline earth metals in waters and carbonate deposits reveals mobile behavior for Mg and Ba. The ratio of strontium to calcium concentrations in solid and liquid phases was found to be almost the same. Li/Cs and B/Cl ratios of waters …


Stream Sediment Geochemical Exploration For Gold In The Kazdağ Dome In The Biga Peninsula, Western Turkey, Hüseyi̇n Yilmaz Jan 2007

Stream Sediment Geochemical Exploration For Gold In The Kazdağ Dome In The Biga Peninsula, Western Turkey, Hüseyi̇n Yilmaz

Turkish Journal of Earth Sciences

The Tuztaşı Au-Ag mineralized system was discovered within the Kazdağ dome using BLEG (bulk leach extractable gold) and 180-µm stream sediment geochemical data collected across the Biga Peninsula in western Turkey. The deposit is located within the hinge of an antiform consisting mainly of high-grade metamorphic and mélange rocks that include the Altınoluk Pb-Zn-Cu-Ag-Au and Evciler Fe-Au-Cu deposits on the southern and on the northern flanks, respectively; no mineralization has been reported prior to this work which was first carried out in 1996 between Altınoluk and Evciler. The BLEG Ag/Au ratios at Tuztaşı (max 87) and Altınoluk (max 43) are …


Sulfur And Lead Isotope Investigations Of The Carbonate-Hosted Pb-Zn Deposits In The Yahyalı Region, Kayseri, Southern Turkey, Osman Koptagel, Ulvi̇ Ulusoy, Anthony E. Fallick Jan 2007

Sulfur And Lead Isotope Investigations Of The Carbonate-Hosted Pb-Zn Deposits In The Yahyalı Region, Kayseri, Southern Turkey, Osman Koptagel, Ulvi̇ Ulusoy, Anthony E. Fallick

Turkish Journal of Earth Sciences

Carbonate-hosted Pb-Zn deposits are common in the Yahyalı region (Taurus Belt) with galena the most abundant sulfide mineral. The mean d34S values for Göynük, Celaldağı Desandre, Demircilik, Tekke, Havadan and Suçatı deposits were +0.2±0.5, +9.3±0.8, +10.7±1.3, +10.8±1.3, +11.5±2.4, -4.2±0.4%o, respectively. The mean 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb measurements for the studied deposits were 18.968±0.005, 15.741±0.005 and 39.074±0.016 for Göynük, 18.702±0.006, 15.715±0.006 and 38.883±0.021 for Celaldağı Desandre, 18.618±0.020, 15.727±0.008 and 38.852±0.032 for Demircilik, 18.808±0.017, 15.751±0.028 and 38.983±0.166 for Suçatı. The sulfur isotope systematics imply that sulfur originated from a mixture of different sources for the Göynük and Suçatı deposits, but was probably …


Effects Of Compaction Parameters On Heavy Metal Mass Transport In Ankara Clay Liner: Experimental Approach, M. Zeki̇ Çamur, Füsun Canpolat, Hasan Yazicigi̇l Jan 2007

Effects Of Compaction Parameters On Heavy Metal Mass Transport In Ankara Clay Liner: Experimental Approach, M. Zeki̇ Çamur, Füsun Canpolat, Hasan Yazicigi̇l

Turkish Journal of Earth Sciences

Mass transports of Cl, Cd, Cr, Cu, Fe, K, Mn, Ni, Pb and Zn ions through the Ankara clay liner was prepared under two different compaction conditions, and were studied experimentally on the bases of sorption and hydrodynamic dispersion processes. According to geotechnical tests, the Ankara clay material is highly plastic, inorganic clay having a liquid limit of 73, a plastic limit of 29 and a plasticity index of 44. Optimum compaction of the material requires 32% water content and 1.413 g/cm^3 dry density. Two materials, prepared using half of the optimum water content but optimum energy conditions (I) and …


A Mineralogical Note On Boulangerite, Geocronite And Yenerite From Near Işık Dağı (Kızılcahamam-Ankara), Turkey, W. E. Sharp, Mark Wieland, Steven K. Mittwede Jan 2007

A Mineralogical Note On Boulangerite, Geocronite And Yenerite From Near Işık Dağı (Kızılcahamam-Ankara), Turkey, W. E. Sharp, Mark Wieland, Steven K. Mittwede

Turkish Journal of Earth Sciences

Microprobe studies have facilitated recognition of the first documented occurrence of geocronite from Işık Dağı (Ankara, Turkey). While yenerite remains a discredited species along the PbS-Sb2S3 compositional join, our analyses show significant arsenic as did the original analyses for yenerite; thus, this name might be retained for arsenic-bearing varieties of boulangerite.


Stratigraphy And Geochemical Features Of The Early Miocene Bimodal (Ultrapotassic And Calc-Alkaline) Volcanic Activity Within The Ne-Trending Selendi Basin, Western Anatolia, Turkey, Yalçin Ersoy, Cahi̇t Helvaci Jan 2007

Stratigraphy And Geochemical Features Of The Early Miocene Bimodal (Ultrapotassic And Calc-Alkaline) Volcanic Activity Within The Ne-Trending Selendi Basin, Western Anatolia, Turkey, Yalçin Ersoy, Cahi̇t Helvaci

Turkish Journal of Earth Sciences

Western Anatolia has experienced thickening and orogenic collapse subsequent to the Eocene continent-arc collision. The early stage of the post-collisional volcanism in the region was thought to have produced widespread lavas and pyroclastic deposits of calc-alkaline basaltic andesite to rhyolite composition. However, in the Selendi Basin, one of the NE-trending basins in western Anatolia, there are two distinct volcanic unit compositions associated with the Lower Miocene sedimentary rocks: (1) a calc-alkaline, high-potassic felsic unit; and (2) alkaline, ultrapotassic lamproitic units, i.e. both are bimodal in character. The calc-alkaline felsic volcanic rocks (Eğreltidağ volcanic unit) are composed of wide-spread pyroclastic rocks …