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Electron Liquid Beyond The Random Phase Approximation, Mehmet Tomak, Ceyhun Bulutay
Electron Liquid Beyond The Random Phase Approximation, Mehmet Tomak, Ceyhun Bulutay
Turkish Journal of Physics
A deeper understanding of low-dimensional and small-scale electronic systems requires an accurate characterization of the many-electron effects. Based on the electron liquid (EL) model, these many-body effects in the three-dimensional (3D) and two-dimensional (2D) electronic systems are dealt going beyond the random phase approximation within the zero-temperature framework. The dielectric formulation of the many-body problem is recapitulated and the longitudinal dielectric function of the EL is obtained using the self-consistent local-field correction scheme, known as STLS, under a general spin-valley degeneracy. Extensive explicit expressions are provided for the use of other researchers. The performance of this formalism is compared in …
Magnetic Excitations In Random Anisotropic Magnets, İbrahim Avgin
Magnetic Excitations In Random Anisotropic Magnets, İbrahim Avgin
Turkish Journal of Physics
A study is made for the magnetic excitations and their Anderson localization properties for a Heisenberg ferromagnet with random anisotropic fields. The system is assumed to be in a strong applied field so that complete spin alignment is established. The magnetic excitations, i.e., the harmonic spin waves, are computed using coherent-field-anisotropy approximation (a version of coherent potential approximation of the electronic problem). The spin wave shift and damping are calculated using the computed coherent field which is a complex function of energy approximating the random medium as a mean field level. The localizaton of the excitations are calculated by adopting …
Three-Channel General-Purpose Astrophotometer, Romualdas Kalytis
Three-Channel General-Purpose Astrophotometer, Romualdas Kalytis
Turkish Journal of Physics
The high-speed three-channel photometer suitable for the time-series observations of the "Whole Earth Telescope" (WET) project as well as for multicolor photometry is described. The photometer, designed for the Capodimonte Astronomical Observatory, Italy, is the latest version of the WET photometers developed by the WET group of Vilnius University since 1992. The main optical and mechanical layouts of the optico-mechanical module as well as the block-diagram of electronics are presented. The main specifications of the photometer expected after its completion are given.
Photometric Imaging With Distributive Solar Analogy, Zeki̇ Eker
Photometric Imaging With Distributive Solar Analogy, Zeki̇ Eker
Turkish Journal of Physics
The importance of DSA (Distributive Solar Analogy) when modeling starspots from a photometric data is discussed. It's advantage over the other modeling techniques to confine the solution parameters, especially the spot latitudes are described. Unlike the other photometric techniques which tries to locate limited number of cool surface spots, DSA aims to model global distribution of all virtually existing spots.
Medium-Dependent Metric In Electrostatics, Bernard Jancewicz
Medium-Dependent Metric In Electrostatics, Bernard Jancewicz
Turkish Journal of Physics
The use of differential forms allows the formulation of the principal equations of electrodynamics in a metric-independent way. The metric is needed only for finding the solutions. Various metrics can be introduced, depending on the medium. A special metric, connected with the electric permittivity tensor, allows us to reduce all electrostatic problems in anisotropic media to those in in isotropic one.
The Wigner Problem In Electrodynamics, Andrzej Horzela
The Wigner Problem In Electrodynamics, Andrzej Horzela
Turkish Journal of Physics
The relation between canonical commutation rules and a shape of acting force is analysed. It is shown that canonical commutation relations and Newtonian equations of motion for a single particle dynamics do imply the force to be of the Lorentz type but the inverse is not true. The example of a single particle motion in a constant magnetic field shows that equations of motion allow an alternative to canonical commutation relations to exist and it is a Lie algebra. The algebra found is of the type of algebras found in studies leading towards noncommutative geometry approaches to physical problems.
Exclusive Disjunctions In Indefinite And Maybe Information In Relational Databases, Taflan İ. Gündem
Exclusive Disjunctions In Indefinite And Maybe Information In Relational Databases, Taflan İ. Gündem
Turkish Journal of Electrical Engineering and Computer Sciences
Incorporating indefinite information into databases has been studied extensively. In this paper, we propose a structure called an E-table to represent maybe information and inclusive and exclusive disjunctions. We define the type of redundancies in E-tables and show how to eliminate them. Also we present an extended relational algebra to operate on E-tables. In this paper we expand the concepts and operations defined by Lin and Sunderraman [1] in order to accommodate exclusive disjunctions in relational databases.
Canonical Framings For 3 -Manifolds, Rob Kirby, Paul Melvin
Canonical Framings For 3 -Manifolds, Rob Kirby, Paul Melvin
Turkish Journal of Mathematics
No abstract provided.
On Symplectic Fillings Of 3-Manifolds, Paola Lisca
On Symplectic Fillings Of 3-Manifolds, Paola Lisca
Turkish Journal of Mathematics
No abstract provided.
Alternative Polynomial And Holomorphic Dunford-Pettis Properties, Walden Freedman
Alternative Polynomial And Holomorphic Dunford-Pettis Properties, Walden Freedman
Turkish Journal of Mathematics
Alternatives to the Polynomial Dunford-Pettis property and the Holomorphic Dunford-Pettis property, called the PDP1 and HDP1 properties, respectively, are introduced. These are shown to be equivalent to the DP1 property, an alternative Dunford-Pettis property previously introduced by the author, thus mirroring the equivalence of the three original properties.
Some Theorems Involving Inequalities On P-Valent Functions, Hüseyi̇n Irmak, Ömer Faruk Çeti̇n
Some Theorems Involving Inequalities On P-Valent Functions, Hüseyi̇n Irmak, Ömer Faruk Çeti̇n
Turkish Journal of Mathematics
In this paper, some theorems involving inequalities on $p$-valent functions (that is $p$-valenty close-to-convex functions, $p$-valently starlike functions, and $p$-valently convex functions) are given. Moreover, some applications in the theorems which are important for geometric function theory are also included. Keywords: Analytic, $p$-valent, $p$-valently colse-to-convex functions, $p$-valently starlike functions, $p$-valently convex functions, open unit disk, and Jack's Lemma.
The Structure Of A Solvmanifold's Heegaard Splittings, Darly Cooper, Martin Scharlemann
The Structure Of A Solvmanifold's Heegaard Splittings, Darly Cooper, Martin Scharlemann
Turkish Journal of Mathematics
No abstract provided.
Tyurina Components And Rational Cycles For Rational Singularities, Meral Tosun
Tyurina Components And Rational Cycles For Rational Singularities, Meral Tosun
Turkish Journal of Mathematics
In this paper, we give a geometric proof of Pinkham's theorem on the positive cycles supported on the exceptional divisor of a rational singularity. In order to do this, we give several properties of the Tyurina components of the exceptional divisor and of the points of blowing-up surface of a rational singularity.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Cover And Contents
Turkish Journal of Veterinary & Animal Sciences
No abstract provided.
Reactions Of N-Aminopyrimidine Derivatives With 1,3-Dicarbonyl Compounds, Zülbi̇ye Önal, Behzat Altural
Reactions Of N-Aminopyrimidine Derivatives With 1,3-Dicarbonyl Compounds, Zülbi̇ye Önal, Behzat Altural
Turkish Journal of Chemistry
The reactions of 1-Amino-pyrimidine derivatives (1) and some 1,3-dicarbonyl compounds (2) were realized in the presence of p-toluensulfonic acid catalyst to give convenient enamine (3) and/or imine derivatives (4). In the same way, the enamine (5) and/or imine derivatives (6) were synthesized using (1) and 1,3-indanedione which is one of the different 1,3-dicarbonyl compounds. The molecular structures of all the prepared compounds were determined by ^1H-nmr, ^{13}C-nmr, i.r. spectra and elemental analyses, and were drawn by taking imine-enamine tautomerism into account.
An Efficient Acetylation Of Primary And Secondary Aliphatic Alcohols With Acetic Anhydride In The Presence Of Graphite Bisulphate, Hasan Seçen, A. Hami̇t Kalpar
An Efficient Acetylation Of Primary And Secondary Aliphatic Alcohols With Acetic Anhydride In The Presence Of Graphite Bisulphate, Hasan Seçen, A. Hami̇t Kalpar
Turkish Journal of Chemistry
In cyclohexane, thirteen examples of primary and secondary aliphatic alcohols were easily converted to the corresponding acetate derivatives within a short time, ranging from 5 min to 2.5 h, and in good yields close to 90%, using acetic anhydride as reagent and graphite bisulphate as an efficient catalyst.
Chemical Constituents Of Centaurea Cuneifolia, Ümi̇t Aslan, Sevi̇l Öksüz
Chemical Constituents Of Centaurea Cuneifolia, Ümi̇t Aslan, Sevi̇l Öksüz
Turkish Journal of Chemistry
The whole plant material fo Centaurea cuneifolia Sm. afforded three sesquiterpene lactones; cnicin (1), dehydromelitensin (2) and dehydromelitensin-8-[(2^{'}-\alpha-hydroxy-\beta- hydroxyethyl)-acryloyl)] (3), the lignan; (-)-arctigenin (4), flavonoids; salvigenin (5), eupatilin (6), jaceosidin (7), acacetin (8), kaemferol (9), 5,7,4^{'}-trihydroxy-3-methylether (10), 5-hydroxy-3^{'},^{'},6,7-tetramethoxyflavone (11) and 5-hydroxy-3^{'},4^{'},7,8-tetramet hoxyflavone (12), a triterpene; \alpha-amyrin and a sterol; \beta-sitosterol. The structures of the isolates were determined by IR, UV, ^1H and ^{13}C NMR and MS spectroscopy.
The Revovery Of Copper And Cobalt From Oxidized Copper Ore And Converter Slag, Berri̇n Zi̇yadanoğullari, Recep Zi̇yadanoğullari
The Revovery Of Copper And Cobalt From Oxidized Copper Ore And Converter Slag, Berri̇n Zi̇yadanoğullari, Recep Zi̇yadanoğullari
Turkish Journal of Chemistry
The aim of this study was to develop a method for obtaining copper and cobalt from oxidized copper ore and converter slag. In order to convert the copper and cobalt into sulfate compounds the main step was to roast the samples obtained by sulfurization and transfer the samples into solution. First the oxidized copper ore was roasted, followed by the mixture of converter slag and oxidized copper ore. Since the levels of copper and cobalt were low, the sulfurization process was carried out under autoclave conditions. The samples obtained were roasted. The yields of copper and cobalt passed into the …
Transition Metal Compound Mediated Reduction Of \Alpha-Amino Acids To 1,2-Amino Alcohols With Nabh_4 In Water, Ayhan S. Demi̇r, İdris M. Akhmedov, Özge Şeşenoğlu
Transition Metal Compound Mediated Reduction Of \Alpha-Amino Acids To 1,2-Amino Alcohols With Nabh_4 In Water, Ayhan S. Demi̇r, İdris M. Akhmedov, Özge Şeşenoğlu
Turkish Journal of Chemistry
A new efficient and cost-effective method for the preparation of 1,2-amino alcohols is described. The reactions of amino acids with NaBH_4 in the presence of NiCl_2 or MoO_3 in water give 1,2-amino alcohols in high yield. When optically pure amino acids were used, optically pure 1,2-amino alcohols were obtained.