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Full-Text Articles in Physical Sciences and Mathematics

Silver Ion-Assisted Ring Expansions In Different Solvent Systems, Mesut Boz, Hafi̇ze Çalişkan, Ömer Zai̇m Jan 2009

Silver Ion-Assisted Ring Expansions In Different Solvent Systems, Mesut Boz, Hafi̇ze Çalişkan, Ömer Zai̇m

Turkish Journal of Chemistry

Several ring expansion products carrying vinylic bromo functionality were synthesized by opening of the geminal dibromobicyclo[n.1.0]alkanes ring. Dibromocarbene was formed from bromoform and potassium tert-butoxide in hexane. Its reaction with various cyclic alkenes was the resultant dibromobicyclo[n.1.0]alkanes. Then, opening was performed using AgNO_3 in various solvent systems, such as acetic acid/DMSO, acetic acid/DMF, CH_3OH/acetone, and H_2O/DMF.


Microwave-Assisted Synthesis Of Some Metal-Free Phthalocyanine Derivatives And A Comparison With Conventional Methods Of Their Synthesis, Özlem Seven, Bi̇rcan Di̇ndar, Burak Gülteki̇n Jan 2009

Microwave-Assisted Synthesis Of Some Metal-Free Phthalocyanine Derivatives And A Comparison With Conventional Methods Of Their Synthesis, Özlem Seven, Bi̇rcan Di̇ndar, Burak Gülteki̇n

Turkish Journal of Chemistry

Synthesis of metal-free 2,9(10),16(17),23(24)-tetra(3,5- dimethylphenoxy) phthalocyanine, 2,9(10),16(17), 23(24)-tetra(4- tert-butylphenoxy) phthalocyanine, and 2,9(10),16(17),23(24)-tetra(3,5- di-tert-butyl-4-hydroxyphenyl) phthalocyanine was carried out via microwave irradiation. Furthermore, pentanol and lithium were used for the first time in the synthesis of metal-free phthalocyanine under microwave irradiation as a solvent and a base-catalyst, respectively. The microwave irradiation experiments were performed in a MARS5 with a CEM XP-1500 vessel. In addition, these compounds were obtained with conventional heating procedures to compare them with those obtained with microwave irradiation. The compounds were characterized by elemental and spectroscopic analysis, including UV-Vis, H NMR, FT-IR, and MALDI-TOF mass data. In particular, both …


Synthesis And Antimicrobial And Antitumor Activity Of Some New [1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Sengül Alpay Karaoğlu Jan 2009

Synthesis And Antimicrobial And Antitumor Activity Of Some New [1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Sengül Alpay Karaoğlu

Turkish Journal of Chemistry

4-[Arylidene-amino]-3-thiophen-2-ylmethyl-4,5-dihydro[1,2,4]triazole-5-one compounds (3a-g) with Schiff base character were obtained from the reaction of 4-amino-3-thiophen-2-ylmethyl-4,5-dihydro-1H-[1,2,4]triazole-5-one (2) with various aldehydes. 1-(2-Oxo-2-phenyl-ethyl)-4-[arylidene-amino]-3-thiophen-2-ylmethyl-4,5- dihydro-1H-[1,2,4]triazole-5-ones (4a-g) were synthesized from the reaction of corresponding compounds 3a-g with bromoacetophenone. 1-(2-Hydroxy-2-phenyl-ethyl)- 3-thiophen-2-ylmethyl-4-[aryl-amino]4,5-dihydro-1H-[1,2,4]triazole-5-ones (5a-g) and 1-(2-hydroxy-2-phenyl-ethyl)-3-thiophen-2-ylmethyl-4-[arylidene-amino] 4,5-dihydro-1H-[1,2,4]triazole-5-ones (6b,d,e) were obtained from the selective reduction of 1-(2-oxo-2-phenyl-ethyl)-4-[arylidene-amino]-3-thiophen-2ylmethyl- 4,5-dihydro-1H-[1,2,4] triazole-5-ones (4) with NaBH_4. They were characterized by IR, H-NMR,^{13}C-NMR, and elemental analyses. Compounds 2, 3a, 3c, 3g, 4f, 5b, and 5g showed good antifungal activity against yeast-like fungi. Compounds selected by the National Cancer Institute (NCI, USA) were investigated for antitumor activity.


Voltammetric Determination Of Ascorbic Acid And Dopamine Simultaneously At A Single Crystal Au(111) Electrode, Zekerya Dursun, Levent Peli̇t, Isao Taniguchi Jan 2009

Voltammetric Determination Of Ascorbic Acid And Dopamine Simultaneously At A Single Crystal Au(111) Electrode, Zekerya Dursun, Levent Peli̇t, Isao Taniguchi

Turkish Journal of Chemistry

A single-crystal Au(111) electrode was used for the simultaneous determination of dopamine (DA) and ascorbic acid (AA) in a phosphate buffer solution at pH 6.9. The single-crystal Au(111) electrode displayed excellent electrocatalytic activity for DA and AA oxidation in comparison to a Au disk electrode. Although the anodic peaks of both reagents overlapped on the Au disk electrode, the anodic peak potentials of DA and AA in their mixture were well separated since the peak potential of AA was shifted to more negative values by cyclic and differential pulse voltammetry. The oxidation peak current increased linearly with the concentration of …


Ferric Hydrogen Sulfate As An Efficient Heterogeneous Catalyst For Environmentally Friendly Greener Synthesis Of 1,8-Dioxo-Octahydroxanthenes, Hamid Reza Shaterian, Asghar Hosseinian, Majid Ghashang Jan 2009

Ferric Hydrogen Sulfate As An Efficient Heterogeneous Catalyst For Environmentally Friendly Greener Synthesis Of 1,8-Dioxo-Octahydroxanthenes, Hamid Reza Shaterian, Asghar Hosseinian, Majid Ghashang

Turkish Journal of Chemistry

Ferric hydrogen sulfate was used as an environmentally friendly heterogeneous acidic catalyst for the greener, 1-pot, 3-component synthesis of 1,8-dioxo-octahydroxanthene via condensation reactions between aromatic aldehydes and dimedone under solvent-free thermal and microwave irradiation as well as in aqueous media conditions in short periods of times with excellent yields. The catalyst was easily separated in simple work-up and was recycled several times without loss of reactivity under the described reaction conditions.


The Effect Of Electrocatalytic Activity And Crystal Structure Of Pbo_2 Surfaces On Polyphenylene Oxide (Ppo) Production In Acetonitrile, Serdar Abaci, Atti̇la Yildiz Jan 2009

The Effect Of Electrocatalytic Activity And Crystal Structure Of Pbo_2 Surfaces On Polyphenylene Oxide (Ppo) Production In Acetonitrile, Serdar Abaci, Atti̇la Yildiz

Turkish Journal of Chemistry

The crystallographic nature of PbO_2 films was changed by optimizing the electrolysis conditions in an electrodeposition solution of PbO_2. These PbO_2 films were then used to prepare PPO films. It was determined that \alpha and \beta modifications, and relative degrees of crystallinity had profound effects on the electrocatalytic performance of PbO_2 films in the production PPO films.


Synthesis Of 5-Arylamino-1h (2h)-Tetrazoles And 5-Amino-1-Aryl-1h-Tetrazoles From Secondary Arylcyanamides In Glacial Acetic Acid: A Simple And Efficient Method, Ali Reza Modarresi-Alam, Mahmoud Nasrollahzadeh Jan 2009

Synthesis Of 5-Arylamino-1h (2h)-Tetrazoles And 5-Amino-1-Aryl-1h-Tetrazoles From Secondary Arylcyanamides In Glacial Acetic Acid: A Simple And Efficient Method, Ali Reza Modarresi-Alam, Mahmoud Nasrollahzadeh

Turkish Journal of Chemistry

A simple and efficient method for the preparation of 5-arylamino-1H (2H)-tetrazoles (3a-i) and 5-amino-1-ary-1H-tetrazoles (4a-i), with excellent yields and high purity, from secondary arylcyanamides (1a-i) at room temperature in glacial acetic acid is described. Tautomers 3a-i were separated from tautomers 4a-i by crystallization in ethanol. A mechanism was introduced in glacial acetic acid. The ratio of isomers is described based on the electronic and steric effects of various substituents. The electron withdrawing group (-NO_2) increased the ratio of 4:3. The rate of product formation was enhanced by introducing electron donating substituents. ^1H-NMR and ^{13}C-NMR chemical shifts and multiplicities are also …


Investigation Of Biodiesel Production From Canola Oil Using Amberlyst-26 As A Catalyst, Oğuzhan İlgen, Ayşe Ni̇lgün Akin, Nezahat Boz Jan 2009

Investigation Of Biodiesel Production From Canola Oil Using Amberlyst-26 As A Catalyst, Oğuzhan İlgen, Ayşe Ni̇lgün Akin, Nezahat Boz

Turkish Journal of Chemistry

The transesterification of canola oil to fatty acid methyl esters was studied using Amberlyst-26 as a solid catalyst. The influence of reaction conditions, such as the reaction time, methanol to oil molar ratio, amount of catalyst, effect of co-solvent, and alcohol and oil types, were determined. When the reaction was carried out at 45 °C with a canola oil to methanol molar ratio of 6:1, a reaction time of 1.5 h, and 3 wt.% of catalyst, oil conversion was about 67%. Methanol was much more reactive than ethanol and isopropyl alcohol (IPA) in the transesterification reaction. The conversion of canola …


Development Of Alumina Supported Alkaline Catalysts Used For Biodiesel Production, Oğuzhan İlgen, Ayşe Ni̇lgün Akin Jan 2009

Development Of Alumina Supported Alkaline Catalysts Used For Biodiesel Production, Oğuzhan İlgen, Ayşe Ni̇lgün Akin

Turkish Journal of Chemistry

The transesterification of canola oil with methanol was studied in a heterogeneous system, using \gamma-Al_2O_3 supported alkaline catalysts. All the catalysts were prepared by incipient-wetness impregnation of an aqueous solution of alkaline compounds on \gamma-Al_2O_3 support. The effects of alkaline compound, methanol/canola oil molar ratio, reaction temperature, catalyst amount, and reaction time in biodiesel production were investigated. The catalyst with KOH loaded on \gamma-Al_2O_3 gave the highest basicity and the best catalytic activity for this reaction. The highest FAME yield obtained was 89.40%.


Local Fourier Bases And Ultramodulation Spaces, Salti Samarah, Fady Hasan Jan 2009

Local Fourier Bases And Ultramodulation Spaces, Salti Samarah, Fady Hasan

Turkish Journal of Mathematics

It was proved that local Fourier bases are unconditional bases for modulation spaces M_{p.q}^w. We prove that the local Fourier bases are unconditional bases for ultramodulation spaces M_p^{w_{\gamma}}=M_{p.p}^{w_{\gamma}}, where 0


Strong Differential Subordination, Georgia Irina Oros, Gheorghe Oros Jan 2009

Strong Differential Subordination, Georgia Irina Oros, Gheorghe Oros

Turkish Journal of Mathematics

The concept of differential subordination was introduced in [4] by S. S. Miller and P. T. Mocanu and the concept of strong differential subordination was introduced in [1] by J. A. Antonino and S. Romaguera. This last concept was applied in the special case of Briot-Bouquet strong differential subordination. In this paper we study the strong differential subordinations in the general case, following the general theory of differential subordinations presented in [4].


A Note On The Lévy Constant For Continued Fractions, Ting Zhong Jan 2009

A Note On The Lévy Constant For Continued Fractions, Ting Zhong

Turkish Journal of Mathematics

In this note, we study the lévy constant of continued fraction expansions. We show that for all x \in [0,1), the upper lévy constant of x is finite except a set with Hausdorff dimension one-half.


Some Properties Of The First Eigenvalue Of The $P(X)$-Laplacian On Riemannian Manifolds, R. A. Mashiyev, Guli̇zar Ali̇soy, Sezai̇ Ogras Jan 2009

Some Properties Of The First Eigenvalue Of The $P(X)$-Laplacian On Riemannian Manifolds, R. A. Mashiyev, Guli̇zar Ali̇soy, Sezai̇ Ogras

Turkish Journal of Mathematics

The main result of the present paper establishes a stability property of the first eigenvalue of the associated problem which deals with the $p(x)$-Laplacian on Riemannian manifolds with Dirichlet boundary condition.


A Perturbation Of M-Order Derivations On Banach Algebras, Yong-Soo Jung, Kyoo-Hong Park Jan 2009

A Perturbation Of M-Order Derivations On Banach Algebras, Yong-Soo Jung, Kyoo-Hong Park

Turkish Journal of Mathematics

Let \A be a unital Banach algebra and let m, 1 \leq m \leq 4, be an integer. If f: \A \to \A is an approximate m-order derivation in the sense of Hyers-Ulam-Rassias, then f: \A \to \A is an exact m-order derivation.


Mineral Chemistry And Petrochemistry Of Post-Collisional Tertiary Mafic To Felsic Cogenetic Volcanics In The Ulubey (Ordu) Area, Eastern Pontides, Ne Turkey, İrfan Temi̇zel, Mehmet Arslan Jan 2009

Mineral Chemistry And Petrochemistry Of Post-Collisional Tertiary Mafic To Felsic Cogenetic Volcanics In The Ulubey (Ordu) Area, Eastern Pontides, Ne Turkey, İrfan Temi̇zel, Mehmet Arslan

Turkish Journal of Earth Sciences

Post-collisional Tertiary volcanic rocks in the Ulubey (Ordu) area at the western edge of the eastern Pontides palaeo-arc are divided into four suites. The Yenisayaca basalt (TB) contains plagioclase (An_{61-83}), clinopyroxene (Wo_{42-44}En_{39-41}Fs_{15-18}) and olivine phenocrysts and titanomagnetite microphenocrysts, whereas the Çatal Tepe and Elekçioğlu Tepe suite (ÇES), Işık Tepe suite (ITS) and andesite/ trachyandesite suite (ATS) rocks include plagioclase (An_{23-78}), clinopyroxene (Wo_{27-48}En_{37-55}Fs_{11-26}), hornblende (Mg#= 0.63-0.76), biotite (Mg#= 0.63-0.82), sanidine phenocrysts and titanomagnetite and apatite microphenocrysts. Petrochemically, the volcanic rocks show tholeiitic-alkaline to the calc-alkaline affinities, and have medium to high-K contents. Most samples have low Mg#, Cr, and Ni, which …


Geochemical Characteristics Of Mafic And Intermediate Volcanic Rocks From The Hasandağ And Erciyes Volcanoes (Central Anatolia, Turkey), Aykut Güçteki̇n, Nezi̇hi̇ Köprübaşi Jan 2009

Geochemical Characteristics Of Mafic And Intermediate Volcanic Rocks From The Hasandağ And Erciyes Volcanoes (Central Anatolia, Turkey), Aykut Güçteki̇n, Nezi̇hi̇ Köprübaşi

Turkish Journal of Earth Sciences

Hasandağ and Erciyes stratovolcanoes, which are the two important stratovolcanoes in Central Anatolia, erupted volcanic products with both calc-alkaline and alkaline compositions, although the calc-alkaline activity is more widespread. There are three stages of geochemical evolution in the history of the Hasandağ stratovolcanic complex: (1) Keçikalesi tholeiitic volcanism, (2) Hasandağ calc-alkaline volcanism, and (3) Hasandağ alkaline volcanism. The geochemical evolution of Erciyes volcanic complex also exhibits three distinct evolutionary stages: (1) Koçdağ alkaline volcanism, (2) Koçdağ calc-alkaline volcanism and (3) Erciyes calc-alkaline volcanism. The volcanic rocks from both suites show enrichments in LREE relative to HREE. The rocks as a …


^{207}Pb-^{206}Pb, ^{40}Ar-^{39}Ar And Fission-Track Geothermochronology Quantifying Cooling And Exhumation History Of The Kaman-Kırşehir Region Intrusions, Central Anatolia, Turkey, Durmuş Boztuğ, Özlem Güney, Matt Heizler, Raymond J. Jonckheer, Marion Tichomirowa, Nazmi̇ Otlu Jan 2009

^{207}Pb-^{206}Pb, ^{40}Ar-^{39}Ar And Fission-Track Geothermochronology Quantifying Cooling And Exhumation History Of The Kaman-Kırşehir Region Intrusions, Central Anatolia, Turkey, Durmuş Boztuğ, Özlem Güney, Matt Heizler, Raymond J. Jonckheer, Marion Tichomirowa, Nazmi̇ Otlu

Turkish Journal of Earth Sciences

The Kaman-Kırşehir region intrusions were generated in a post-collisional extensional setting following Cenomanian-Turonian docking of an oceanic island arc, comprising the supra-subduction zone (SSZ) Central Anatolian ophiolite (CAO), onto the Tauride-Anatolide Platform (TAP). These granitoids have been named, from N to S, the Çamsarı quartz syenite, Hamit quartz syenite, Bayındır nepheline-cancrinite syenite, Durmuşlu nepheline-nosean-melanite syenite porphyry and Baranadağ quartz monzonite. They intrude the crustal metasediments of the Central Anatolian Crystalline Complex (CACC) and CAO and are unconformably overlain by Upper Paleocene to Lower-Middle Eocene sediments. The single-zircon ^{207}Pb-^{206}Pb evaporation age of the Çamsarı unit is 95.7±5.1 Ma; those of the …


Analytical Regularization Method For Electromagnetic Wave Diffraction By Axially Symmetrical Thin Annular Strips, Fati̇h Di̇kmen, Yury Alexanderovich Tuchkin Jan 2009

Analytical Regularization Method For Electromagnetic Wave Diffraction By Axially Symmetrical Thin Annular Strips, Fati̇h Di̇kmen, Yury Alexanderovich Tuchkin

Turkish Journal of Electrical Engineering and Computer Sciences

A new mathematically rigorous and numerically efficient method based on the combination of Orthogonal Polynomials Method, and Analytical Regularization Method, for electromagnetic wave diffraction by a model structure for various antennae such as Fresnel zone plates is proposed. It can be used as validation tool for the other (more general or less accurate) numerical methods and physical approaches. The initial boundary value problem is equivalently reduced to the infinite system of the linear algebraic equations of the second kind, i.e. to an equation of the type (I+H) x=b in the space l_2 with compact operator H. This equation can be …


Emc Education At The University Of Technology Zurich, Gökhan Apaydin, Ni̇yazi̇ Ari Jan 2009

Emc Education At The University Of Technology Zurich, Gökhan Apaydin, Ni̇yazi̇ Ari

Turkish Journal of Electrical Engineering and Computer Sciences

This paper illustrates educational issues in electromagnetic compatibility (EMC) engineering in Switzerland and presents the contents of courses and practical materials for EMC education at the University of Technology Zurich. After giving the fundamentals of theoretical part, practical applications have been given to make students and engineers aware of EMC issues and its problems.


U-Pb Zircon Shrimp Ages, Geochemical And Sr-Nd Isotopic Compositions Of The Early Cretaceous I-Type Sarıosman Pluton, Eastern Pontides, Ne Turkey, Abdullah Kaygusuz, Bin Chen, Zafer Aslan, Wolfgang Siebel, Cüneyt Şen Jan 2009

U-Pb Zircon Shrimp Ages, Geochemical And Sr-Nd Isotopic Compositions Of The Early Cretaceous I-Type Sarıosman Pluton, Eastern Pontides, Ne Turkey, Abdullah Kaygusuz, Bin Chen, Zafer Aslan, Wolfgang Siebel, Cüneyt Şen

Turkish Journal of Earth Sciences

The petrogenesis and U-Pb SHRIMP zircon ages of the Late Cretaceous Sarıosman pluton in the Eastern Pontides is investigated by means of whole-rock Sr-Nd isotope data with field, petrographic and whole-rock geochemical studies. The bulk of the I-type Sarıosman pluton consists of biotite-hornblende monzogranite, with minor quantities of porphyritic hornblende-biotite monzogranite. The biotite-hornblende monzogranite contains a number of mafic microgranular enclaves (MMEs) of quartz monzodiorite composition. U-Pb zircon sensitive high-resolution ion microprobe dating (SHRIMP) dates the magma emplacement age of the biotite-hornblende monzogranite at 82.7±1.5 Ma. The rocks of the pluton show high-K calc-alkaline, metaluminous to slightly peraluminous characteristics, and …


A Novel Ep Approach For Multi-Area Economic Dispatch With Multiple Fuel Options, P. S. Manoharan, P. S. Kannan, V. Ramanathan Jan 2009

A Novel Ep Approach For Multi-Area Economic Dispatch With Multiple Fuel Options, P. S. Manoharan, P. S. Kannan, V. Ramanathan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a novel approach to multi-area economic dispatch problems with multiple fuel options using a hybrid evolutionary programming method. The objective is to minimize the operation cost of the entire system while satisfying the tie line constraints. In this paper, EP-LMO (Evolutionary Programming with Levenberg-Marquardt Optimization) technique is proposed to solve multi-area economic dispatch problems with multiple fuel options. The EP-LMO is developed in such a way that a simple evolutionary programming (EP) is applied as a base level search to find the direction of the optimal global region. And Levenberg-Marquardt Optimization (LMO) method is used as a …


Electronic Differential With Direct Torque Fuzzy Control For Vehicle Propulsion System, Kada Hartani, Mohamed Bourahla, Yahia Miloud, Mohamed Sekour Jan 2009

Electronic Differential With Direct Torque Fuzzy Control For Vehicle Propulsion System, Kada Hartani, Mohamed Bourahla, Yahia Miloud, Mohamed Sekour

Turkish Journal of Electrical Engineering and Computer Sciences

We model an electronic differential that will offer the best vehicle stability on a curved road. The proposed traction system consists of two permanent magnet synchronous (PMS) machines that ensure the drive of two back-driving wheels. The contribution of each wheel to the advance of the vehicle is represented by an element conveying the accumulation of mechanical coupling. The proposed control structure is based on the direct torque fuzzy control for each wheel-motor. Different simulations have been carried out: vehicle driven ons straight road, vehicle driven on straight road with slope, and vehicle driven over a road curved left and …


Cdm Based Controller Design For Nonlinear Heat Exchanger Process, Erkan İmal Jan 2009

Cdm Based Controller Design For Nonlinear Heat Exchanger Process, Erkan İmal

Turkish Journal of Electrical Engineering and Computer Sciences

Most processes are nonlinear, and their control is a difficult yet important problem. The heat exchanger is an example onesuch nonlinear process. In the present paper, the effect of process nonlinearity on the performance of set point tracking and disturbance rejection in two controller methods is investigated. Initially, afirst order plus dead time (FOPDT) model of the process is obtainedvia a software known as Loop-Pro Trainer. Then, the PI-controller tuning values are computed using the internal model control (IMC) correlations based on truncated (first-order) Taylor series approximation. Next, another controller is designed using the coefficient diagram method (CDM). Finally, the …


Electromagnetic Compatibility Engineering Education: Problems, Challenges And Perspectives, Levent Sevgi̇ Jan 2009

Electromagnetic Compatibility Engineering Education: Problems, Challenges And Perspectives, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

Education and training problems and challenges in EMC Engineering are discussed. The necessity of physics-based modeling (theory) and hands-on training (practice) are emphasized. An introductory level EMC lecture and a short course outline are given for modern EMC education.


Two Dimensional Ebg Structures For Multiband Noise Mitigation, Antonio Orlandi, Antonio Ciccomancini Jan 2009

Two Dimensional Ebg Structures For Multiband Noise Mitigation, Antonio Orlandi, Antonio Ciccomancini

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper a two dimensional (2D) electromagnetic Bandgap (EBG) structure is proposed for multi band noise mitigation in PWR/GND plane pairs. Excellent noise suppression (-60 dB) is achieved in multiple bands within the range 0--8 GHz with a low start frequency. Because of the 2D EBG, no additional metal layer is required. Signal Integrity analysis is also studied by modelling a microstrip to stripline transition (both single ended and differential) and by evaluating insertion loss, TDR as well as eye diagram.


Vlsi-Cell Placement Technique For Architecture Of Field Programmable Gate Array (Fpga) Design, Avnesh Verma, Sunil Dhingra, M. K. Soni Jan 2009

Vlsi-Cell Placement Technique For Architecture Of Field Programmable Gate Array (Fpga) Design, Avnesh Verma, Sunil Dhingra, M. K. Soni

Turkish Journal of Electrical Engineering and Computer Sciences

The Field Programmable Gate Array (FPGA) is an on field programmable device which can be designed for different applications. Various types of software are available for its synthesis. The cell placement depends upon the designing and programming languages used for FPGA. In this paper cell placement technique of FPGA architecture is analyzed for the application of Space Vector Pulse Width Modulation (SVPWM) technique used in speed control of an induction motor. The modulation pulses are produced due to the various components activated and their interconnection in Configurable Logic Blocks (CLBs). Few of its components are so analyzed to find out …


Electromagnetic Radiation From Multilayer Printed Circuit Boards: A 3d Fdtd-Based Virtual Emission Predictor, Gonca Çakir, Mustafa Çakir, Levent Sevgi̇ Jan 2009

Electromagnetic Radiation From Multilayer Printed Circuit Boards: A 3d Fdtd-Based Virtual Emission Predictor, Gonca Çakir, Mustafa Çakir, Levent Sevgi̇

Turkish Journal of Electrical Engineering and Computer Sciences

A novel FDTD-based virtual electromagnetic compatibility tool for the prediction of electromagnetic emissions from a multilayer printed circuit board is introduced. Tests are performed with characteristic structures and sample simulation results are presented.


Lead And Sulfur Isotope Studies Of The Koru (Çanakkale, Turkey) Lead-Zinc Deposits, Gülcan Bozkaya, Ahmet Gökçe Jan 2009

Lead And Sulfur Isotope Studies Of The Koru (Çanakkale, Turkey) Lead-Zinc Deposits, Gülcan Bozkaya, Ahmet Gökçe

Turkish Journal of Earth Sciences

Koru (Çanakkale) barite-bearing lead-zinc deposits are typical examples of the lead-zinc deposits occurring in the Tertiary volcanic rocks which crop out in the Biga Peninsula. Volcanic rocks around the investigated deposits are distinguished as Eocene Akçaalan andesite, Oligocene Adadağı pyroclastics, Miocene Dededağ dacite and Plio-Quaternary Karaömerler basalt. The investigated deposits are hosted by Adadağı pyroclastics and show two different mineralization styles such as stockwork ore veinlets in the upper parts and ore veins along the fault zones in WNW-ESE direction, in the lower parts. Sphalerite, galena, pyrite, chalcopyrite, quartz, barite and calcite are the main minerals and they are accompanied …


Whole Rock And Mineral Chemistry Of Ultramafic-Mafic Cumulates From The Orhaneli (Bursa) Ophiolite, Nw Anatolia, Ender Sarifakioğlu, Hayretti̇n Özen, John A. Winchester Jan 2009

Whole Rock And Mineral Chemistry Of Ultramafic-Mafic Cumulates From The Orhaneli (Bursa) Ophiolite, Nw Anatolia, Ender Sarifakioğlu, Hayretti̇n Özen, John A. Winchester

Turkish Journal of Earth Sciences

The Orhaneli ophiolite, situated in the western part of the İzmir-Ankara-Erzincan Suture Zone (İAESZ) and south of Bursa, exposes cumulates belonging to the mantle-crust transition zone. The Orhaneli ophiolite consists mainly of ultramafic cumulates and subordinate mafic cumulates. The basal cumulate sequence comprises dunites locally interlayered with chromitite levels. Above, dunitic cumulates, commonly interbanded with cumulate wehrlites, grade up into two pyroxene peridotites (cumulate lherzolites showing some transition to cumulate harzburgites in places). The observation of cumulate gabbroic thin layers intercalated with ultramafic cumulates at least three times suggests that the magma chamber was periodically replenished by basaltic liquids. Petrographic …


Two-And-Three-Dimensional Crustal Thickness Of The Eastern Pontides (Ne Turkey), Nafiz Maden, Kenan Geli̇şli̇, Yener Eyüboğlu, Osman Bektaş Jan 2009

Two-And-Three-Dimensional Crustal Thickness Of The Eastern Pontides (Ne Turkey), Nafiz Maden, Kenan Geli̇şli̇, Yener Eyüboğlu, Osman Bektaş

Turkish Journal of Earth Sciences

The Eastern Pontide orogenic belt is divided into three subzones (northern, southern and axial zones) based on present lithologies and facies associations. NE-SW-, NW-SE- and E-W-trending fault systems, which play an important role in palaeotectonics and neotectonics of the Eastern Pontides, separate these zones. Three different methods were used to estimate the Moho depth from observed gravity value, namely (i) empirical relationship between Moho depth and Bouguer anomaly; (ii) spectral analysis of the radial wave number and; (iii) by the gravity inversion method. Power spectrum, a statistical approach, is a widely used technique to determine the depth of geological sources …