Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 8311 - 8340 of 10319

Full-Text Articles in Physical Sciences and Mathematics

A Molecular Dynamics Study Of The Static Structure, Thermodynamic And Transport Properties Of Liquid Iron Using The Modified Analytic Embedded Atom Method, Serap Şentürk Dalgiç, İbrahi̇m Koçoğlu Jan 2006

A Molecular Dynamics Study Of The Static Structure, Thermodynamic And Transport Properties Of Liquid Iron Using The Modified Analytic Embedded Atom Method, Serap Şentürk Dalgiç, İbrahi̇m Koçoğlu

Turkish Journal of Physics

Using the modified analytic embedded atom method (MAEAM), we have carried out molecular dynamics (MD) simulation to compute structure,thermodynamic and transport properties of liquid iron. The Foiles type effective pair potential based on the MAEAM potential functions proposed by Quyang and co-workers are shown to predict the pair distribution function well near its melting. The calculated thermodynamic properties such as, the internal energy, Helmholtz free energy and entropy are in a good agreement with experimental data. The results for the computed self-diffusion coefficients are in reasonable agreement with experiments and other works.


Non-Commutative And Non-Anticommutative Supersymmetric U(1) Gauge Theories, Kayhan Ülker Jan 2006

Non-Commutative And Non-Anticommutative Supersymmetric U(1) Gauge Theories, Kayhan Ülker

Turkish Journal of Physics

We introduce a parent action for component fields of N=1 supersymmetric U(1) gauge theory in four dimensions which generates both the original and the (s-) dual supersymmetric actions. By using the noncommutative and nonanticommutative deformations of this theory we propose the corresponding parent actions as generalizations of the ordinary case. We then show that duality symmetry under the interchange of fields with duals accompanied by the replacement of the noncommutativity and nonanticommutativity parameters in a suitable way.


Hamilton-Jacobi Formulation Of Siegel Superparticle, N. I. Farahat, Hanaa A. Elegla Jan 2006

Hamilton-Jacobi Formulation Of Siegel Superparticle, N. I. Farahat, Hanaa A. Elegla

Turkish Journal of Physics

The Hamilton-Jacobi formalism of constrained systems is used to study Siegel superparticles moving in R^{4 mid 4} flat superspace. The equations of motion for a singular system are obtained as total differential equations in many variables. These equations of motion are in exact agreement with those obtained by Dirac's method.


Comment On "Characterization Of In_4te_3 Single Crystals", M. Cankurtaran, H. Çeli̇k Jan 2006

Comment On "Characterization Of In_4te_3 Single Crystals", M. Cankurtaran, H. Çeli̇k

Turkish Journal of Physics

No abstract provided.


On Reduced And Semicommutative Modules, Muhi̇tti̇n Başer, Nazim Agayev Jan 2006

On Reduced And Semicommutative Modules, Muhi̇tti̇n Başer, Nazim Agayev

Turkish Journal of Mathematics

In this paper, various results of reduced and semicommutative rings are extended to reduced and semicommutative modules. In particular, we show: (1) For a principally quasi-Baer module, M_R is semicommutative if and only if M_R is reduced. (2) If M_R is a p.p.-module then M_R is nonsingular.


Analysis Of Nanoparticle Transmission Electron Microscopy Data Using A Public- Domain Image-Processing Program, Image, Gerd H. Woehrle, James E. Hutchison, Sai̇m Özkar, Richad G. Finke Jan 2006

Analysis Of Nanoparticle Transmission Electron Microscopy Data Using A Public- Domain Image-Processing Program, Image, Gerd H. Woehrle, James E. Hutchison, Sai̇m Özkar, Richad G. Finke

Turkish Journal of Chemistry

The need to easily and quickly count larger numbers of nanoparticles, in order to obtain statistically useful size and size-distribution data, is addressed via the use of a readily available, free, public-domain program for particle counting, NIH-Image (and 2 others derived from it, Scion Image and Image J), collectively referred to herein as Image. The best protocols that we have found useful for the use of Image are reported; both appropriate as well as problematic applications of Image are then illustrated with a series of TEM images of Ir(0), Pd(0) and Au(0) nanoclusters. Methods to detect and image nanoclusters with …


Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean Jan 2006

Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean

Turkish Journal of Chemistry

Acrylic dispersions based on polyaniline were obtained and characterised. The polyaniline was obtained by chemical polymerisation of aniline in different organic acid containing phosphorous, in the presence of ammonium-peroxidisulphate as oxidant agent. The blends were obtained by mechanical dispersion of polyaniline in commercially available acrylic resin. The flow behaviour of these dispersions at different shear rates was studied. Furthermore, the resulting acrylic dispersions were analysed by IR spectroscopy, and were characterised in terms of their electrical resistance and rheological behaviour


Synthesis And Crystal Structure Of 1,3-Bis(5-Formylpyrrol-2-Yl)Benzene And Its Conversion To A Macrocyclic Derivative, M. Kasim Şener, Davi̇d Sanches Garcia, Mehmet Akkurt, Sema Öztürk Yildirim, Hoong-Kun Fun, Jonathan L. Sessler Jan 2006

Synthesis And Crystal Structure Of 1,3-Bis(5-Formylpyrrol-2-Yl)Benzene And Its Conversion To A Macrocyclic Derivative, M. Kasim Şener, Davi̇d Sanches Garcia, Mehmet Akkurt, Sema Öztürk Yildirim, Hoong-Kun Fun, Jonathan L. Sessler

Turkish Journal of Chemistry

This report details the synthesis and characterization of a new diformyl pyrrole derivative 2 and its macrocyclic derivative 3. The new compounds were characterized by FT-IR, ^{13}C NMR, and ^1H NMR spectroscopies and via mass spectrometric analysis. The structure of 2 in the solid state was determined using X-ray diffraction methods (monoclinic, P2_1/c, a = 17.3760(7), b = 4.9719(2), c = 15.5374(5) Å, \beta = 105.892(2) °, V = 1291.00(9) Å^3, and Z = 4). The molecular structure is stabilized by N-H...O and C-H...O intermolecular hydrogen bonds. The present bisformylpyrrole derivative 2 provides a new precursor that may be useful …


A Miocene Palaeovalley Network In The Western Taurus (Turkey), Olivier Monod, Catherina Kuzucuoğlu, Aral İ. Okay Jan 2006

A Miocene Palaeovalley Network In The Western Taurus (Turkey), Olivier Monod, Catherina Kuzucuoğlu, Aral İ. Okay

Turkish Journal of Earth Sciences

Lower Miocene conglomerates in the Köprü and Manavgat basins contain pebbles that can be confidently traced back to their source areas, owing to their distinctive lithologies. Among others, are the green Huğlu volcanics (Late Trias), known only in allochthonous units from the Beyşehir region, or the Alanya blueschists, restricted to the Sugözü unit in the Alanya Massif. The problem is to find out how this detrital material could have travelled about eighty kilometres through the Taurus calcareous units during the Miocene. Fortunately, the present drainage system is not yet fully reorganised in the Taurus, and large areas of the chain …


Preparation And Characterization Of An Aromatic Polyimide And Its Use As A Selective Membrane For H_2o_2, Ergun Eki̇nci̇, Süleyman Köytepe, Azi̇z Paşahan, Turgay Seçki̇n Jan 2006

Preparation And Characterization Of An Aromatic Polyimide And Its Use As A Selective Membrane For H_2o_2, Ergun Eki̇nci̇, Süleyman Köytepe, Azi̇z Paşahan, Turgay Seçki̇n

Turkish Journal of Chemistry

Selectivity behavior to electroactive and non-electroactive substances of a polyimide prepared from 2,2'-dimethyl-4,4'-diaminobiphenyl and the corresponding dianhydride was examined by electrochemical methods. From the excellent electrochemical findings obtained, it was observed that polyimide film was only permeable to hydrogen peroxide among the substances examined. Therefore, it is claimed that the mentioned polymeric film can be successfully used as a hydrogen peroxide-selective membrane in the presence of electroactive and non-electroactive interferents.


Volcanism And Its Contribution To Mudrock Genesis, Warren Huff Jan 2006

Volcanism And Its Contribution To Mudrock Genesis, Warren Huff

Turkish Journal of Earth Sciences

Explosive eruptions from volcanoes are recorded in the stratigraphic record throughout the Phanerozoic. The most visible evidence of these eruptions is generally in the form of preserved tephra layers, and they appear to be concentrated in the stratigraphic record at times of active plate collision and concomitant high stands of sea level. The products of volcanic eruptions are lavas, tephra and gases, and whereas low-silica, anhydrous basaltic magmas are usually erupted in the form of lava flows high-silica, hydrous rhyolitic magmas are commonly explosively erupted as plinian and ultraplinian plumes, and associated pyroclastic flows. Fallout tephras may be preserved in …


3d-Architecture And Neogene Evolution Of The Malatya Basin: Inferences For The Kinematics Of The Malatya And Ovacık Fault Zones, Nuretdi̇n Kaymakçi, Murat İnceöz, Pinar Ertepinar Jan 2006

3d-Architecture And Neogene Evolution Of The Malatya Basin: Inferences For The Kinematics Of The Malatya And Ovacık Fault Zones, Nuretdi̇n Kaymakçi, Murat İnceöz, Pinar Ertepinar

Turkish Journal of Earth Sciences

The 3D-architecture of the Malatya Basin was studied using remote sensing, seismic interpretation, and palaeostress analysis in the context of the Malatya-Ovacık fault zone. The results indicate that the Ovacık and Malatya fault zones are not different segments of a single 'so called' Malatya-Ovacık fault zone; rather, they are two different fault zones that have operated independently. In addition, the Ovacık fault zone is delimited in the west by the Malatya fault zone, which extends farther north from the point of supposed junction. Maximum individual deflection of streams along the Ovacık fault zone is about 9.3 km, and summation of …


Trace Element Determination In Brassica Oleraceae Var. Acephale By Differential Pulse Polarography, Güler Somer, Arzu Nakişci Ünlü, Şükrü Kalayci, Ferat Şahi̇n Jan 2006

Trace Element Determination In Brassica Oleraceae Var. Acephale By Differential Pulse Polarography, Güler Somer, Arzu Nakişci Ünlü, Şükrü Kalayci, Ferat Şahi̇n

Turkish Journal of Chemistry

A fast and simple differential pulse polarographic (DPP) method for the determination of trace elements in a certain form of cabbage is described. This vegetable is commonly used as food in Turkey, especially in the Black Sea region. Using DPP polarograms of wet digested cabbage samples (leaf) in pH 2 and 4 acetate buffer Mo, Cr, Se, Pb, As and Zn quantities were determined. The best separation and determination condition for Cu and Fe was in EDTA at pH 6.5, and for Ni and Zn it was ammonia buffer at pH 9.8. The trace element quantities in digested leaf samples …


Short And Effective Synthesis Of A Thiophene Analogue Of (\Pm)-4-Ipomeanol And Its Biological Evaluation, Jurgen Krauss, Doris Unterreitmeier, Franz Bracher Jan 2006

Short And Effective Synthesis Of A Thiophene Analogue Of (\Pm)-4-Ipomeanol And Its Biological Evaluation, Jurgen Krauss, Doris Unterreitmeier, Franz Bracher

Turkish Journal of Chemistry

The thiophene analogue of (\pm)-4-ipomeanol (1) was prepared in 2 steps starting from 3-iodothiophene and pent-4-yn-2-ol. The key steps were a Sonogashira reaction, followed by HgO catalysed hydratisation of the triple bond. The resulting thiophene was tested in the MTT assay for its cytotoxic activity against HL 60 cells.


Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay Jan 2006

Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay

Turkish Journal of Earth Sciences

No abstract provided.


Synthesis, Spectral And Thermal Characteristics Of Some Ten Coordinated Complexes Of Dioxouranium(Vi) Derived From Semicarbazones As Primary Ligand And Diphenyl Sulfoxide As Secondary Ligand, Ram K. Agarwal, Surendra Prasad Jan 2006

Synthesis, Spectral And Thermal Characteristics Of Some Ten Coordinated Complexes Of Dioxouranium(Vi) Derived From Semicarbazones As Primary Ligand And Diphenyl Sulfoxide As Secondary Ligand, Ram K. Agarwal, Surendra Prasad

Turkish Journal of Chemistry

The reactions of dioxouranium(VI) acetate with several semicarbazones derived from 4-aminoantipyrine in the presence of diphenyl sulfoxide (DPSO) led to the formation of complexes corresponding to the formulae [UO_2(CH_3COO)_2 (L).DPSO], where L = 4[N-(benzalidene)amino]antipyrinesemicarbazone (BAAPS), 4[N-(2'-hydroxybenzalidene)- amino]antipyrinesemicarbazone (HBAAPS) 4[N-(4'-methoxybenzalidene)amino] antipyrine semicarbazone (MBAAPS) 4[N-(4'-dimethylaminobenzalidene)amino]- antipyrinesemicarbazone (DABAAPS) 4[N-(2'-nitrobenzalidene)amino]antipyrine- semicarbazone (2'-NO_2 BAAPS) 4[N-(3'-nitrobenzalidene)amino]antipyrine- semicarbazone (3'-NO_2BAAPS) 4[N-(4'-nitrobenzalidene)amino]antipyrine- semicarbazone (4'-NO_2BAAPS), 4[N-(4'-hydroxy-3'-methoxybenzalidene)amino]- antipyrinesemicarbazone (HMBAAPS) 4[N-(2'-hydroxy-1'-naphthalidene)amino]- antipyrinesemicarbazone (HNAAPS) 4[N-(cinnamalidene)amino]antipyrine- semicarbazone (CAAPS)4[N-(3',4',5'-trimethoxybenzalidene)amino]antipyrine- semicarbazone (TMBAAPS) and 4[N-(furfural)amino]antipyrinesemicarbazone (FFAAPS). The complexes were characterised by means of elemental analyses, conductivity measurements, molecular weight, magnetic moments and infrared studies. The coordination number 10 is proposed for these complexes. Thermal properties of the …


Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner Jan 2006

Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner

Turkish Journal of Chemistry

A series of novel highly functionalized benzoylaminocarbothioyl pyrrolidines were prepared from benzoylisothiocyanate and substituted pyrrolidines in excellent yield. The crystal structure of the novel 1-benzoylaminocarbothioyl-5-(naphthyl)- pyrrolidine-2,3,4-tricarboxylicacid trimethyl ester (3a) was determined by X-ray crystal structure analysis. The synthesized compounds were characterized and screened for their in vitro antibacterial and antifungal activities and toxicity. The prepared compounds were tested against the standard strains: Escherichia coli (ATCC 25922), Enterobacter cloacae (ATCC 13047), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 29213) and Staphylococcus epidermidis (ATCC 12228) and the yeasts Candida albicans (ATCC 90028), Candida krusei (ATCC 6258), Candida parapsilosis …


Synthesis Of Vic-Dioxime Derivatives With Hydrazone Side Groups And Their Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli Jan 2006

Synthesis Of Vic-Dioxime Derivatives With Hydrazone Side Groups And Their Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli

Turkish Journal of Chemistry

Two novel vic-dioxime (L^1H_2, L^2H_2) compounds bearing hydrazone side groups and their transition metal complexes Ni(II), Co(II), Cu(II), and Zn(II) were synthesized. The vic-dioxime ligands bearing hydrazone side groups were synthesized by reacting anti-glyoximehydrazine (GH_2) with 4-nitroacetophenone and 4-methylacetophenenone, respectively. Ligands form mononuclear complexes [(LH)_2M] with a metal to ligand ratio of 1:2 with M=Co(II)(H_2O)_2, Ni(II), and Cu(II). Zn(II) forms complexes [(LH)(H_2O)(Cl)Zn] with a metal to ligand ratio of 1:1. The Co(II) complexes of the ligands are proposed to be octahedral with water molecules as axial ligands, the Ni(II) and Cu(II) complexes are proposed to be square planar, and the …


Electrochemical Copolymerization Of Thiophene Containing Pseudo-Polyether Cages With Pyrrole, Ati̇lla Ci̇haner, Ahmet M. Önal Jan 2006

Electrochemical Copolymerization Of Thiophene Containing Pseudo-Polyether Cages With Pyrrole, Ati̇lla Ci̇haner, Ahmet M. Önal

Turkish Journal of Chemistry

Conducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (I). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF_6) dissolved in acetonitrile. The spectroelectrochemical properties of the films were investigated using UV-VIS spectroscopy.


Pullbacks Of Crossed Modules And Cat^1- Commutative Algebras, Murat Alp Jan 2006

Pullbacks Of Crossed Modules And Cat^1- Commutative Algebras, Murat Alp

Turkish Journal of Mathematics

In this paper we first review the definitions of crossed module [10], pullback crossed module and cat^1-object in the category of commutative algebras. We then describe a certain pullback of cat^1- commutative algebras.


Profiling Of Lithium And Potassium Into Silicon, Ali M. Mousa Jan 2006

Profiling Of Lithium And Potassium Into Silicon, Ali M. Mousa

Turkish Journal of Physics

The profiling of Lithium and Potassium into Silicon doped by electro deposition from molten salts (LiBr, KI) has been studied for various time periods and deposition currents. For the samples studied, changes in the deposition time and current have significant effects on the conductivity type and sheet resistance variation. This has been attributed to the high value of solid solubility of Lithium and Potassium in Silicon. Additionally, surface concentration variation with depth is affected significantly by variation in deposition time, particular for samples with a deposition time of 7 minutes. A junction was found 156 microns from the surface. For …


Inexpensive Near-Ir Photodetector, Omar A. Abdulrazaq, Evan T. Saleem Jan 2006

Inexpensive Near-Ir Photodetector, Omar A. Abdulrazaq, Evan T. Saleem

Turkish Journal of Physics

Fabrication and characterization of a CdS/Si heterojunction detector for 1.064 \mu m Nd:YAG laser detection has been carried out by pyrolytic spraying of CdS films onto single crystal n-type Si substrates. Response time has been determined in this study.


Transient Photoconductivity In Amorphous Se-Ge-Ag System, R. S. Sharma, D. Kumar, A. Kumar Jan 2006

Transient Photoconductivity In Amorphous Se-Ge-Ag System, R. S. Sharma, D. Kumar, A. Kumar

Turkish Journal of Physics

Transient Photoconductivity measurements have been made in vacuum evaporated thin films of Se_{0.80 - x}Ge_{0.20}Ag_x at different intensities, temperatures and illumination times. The films exhibit long-lived residual photoconductivity, called persistent photoconductivity, with an extremely slow decay rate. The persistent photoconductivity (PPC) increases with an increase in intensity and illumination time. However, this quantity decreases with increase in temperature. These results indicate that the decay of photoconductivity is not only governed by the carrier trapped in the intrinsic defects but also gets affected by the light induced defect creation through structural changes The persistent photoconductivity effect is found to be suppressed …


Stagnation Point Flow And Heat Transfer Of A Micropolar Fluid In A Porous Medium, Hazem Ali Attia Jan 2006

Stagnation Point Flow And Heat Transfer Of A Micropolar Fluid In A Porous Medium, Hazem Ali Attia

Turkish Journal of Physics

The steady laminar flow in a porous medium of an incompressible non-Newtonian micropolar fluid impinging on a permeable flat plate with heat transfer is investigated. A numerical solution for the governing nonlinear momentum and energy equations is obtained. The effect of the porosity of the medium and the characteristics of the non-Newtonian fluid on both the flow and heat transfer is presented and discussed.


Ensemble Teleportation, Thomas Krüger Jan 2006

Ensemble Teleportation, Thomas Krüger

Turkish Journal of Physics

The possibility of teleportation is by sure the most interesting consequence of quantum non-separability. So far, however, teleportation schemes have been formulated by use of state vectors and considering individual entities only. In the present article the feasibility of teleportation is examined on the basis of the rigorous ensemble interpretation of quantum mechanics (not to be confused with a mere treatment of noisy EPR pairs) leading to results which are unexpected from the usual point of view.


Pendant ^{13}C Nmr Spectroscopy Applied To Ch_N Groups, Azmi̇ Gençten, İrfan Şaka, Sedat Gümüş Jan 2006

Pendant ^{13}C Nmr Spectroscopy Applied To Ch_N Groups, Azmi̇ Gençten, İrfan Şaka, Sedat Gümüş

Turkish Journal of Physics

Polarization enhancement nurtured during attached nucleus testing (PENDANT) NMR spectroscopy gives signals of quaternary carbon atoms in addition to signals indicative of CH, CH_2 and CH_3 groups. In this study, using product operator theory, analytical description of PENDANT NMR spectroscopy for CH_n (IS_n, I = 1/2, S = 1/2, n = 0, 1, 2, 3) spin systems are presented. Simulation and experimental results of PENDANT NMR spectroscopy are also presented. Theoretical results are found to be in exact agreement with the simulation results and in good agreement with the experimental ones.


Self-Assembled Nano-Structures On The Icosahedral Al-Pd-Mn Quasicrystal, Mehmet Erbudak, Jean-Nicolas Longchamp, Yves Weisskopf Jan 2006

Self-Assembled Nano-Structures On The Icosahedral Al-Pd-Mn Quasicrystal, Mehmet Erbudak, Jean-Nicolas Longchamp, Yves Weisskopf

Turkish Journal of Physics

A quasicrystal is a solid with an aperiodic atomic distribution, but displaying discrete diffraction pattern. At an interface where an ordinary crystal and a quasicrystal intersect, the lack of commensurability between the structures leads to misfits on atomic scale resulting in a wealth of novelties. Here, we present experimental observations on three essentially different cases: Al, Fe, and Si ultra-thin layers grown in vacuum on the pentagonal surface of an icosahedral Al-Pd-Mn quasicrystal. In all three cases, the growing layer decays into nm-size islands. Al is the major alloy component of the substrate material and provides a natural tool to …


Computational Studies On Mechanical Properties Of Carbon Nanotori, Tahi̇r Çağin, Guanghua Gao, William A. Goddard Iii Jan 2006

Computational Studies On Mechanical Properties Of Carbon Nanotori, Tahi̇r Çağin, Guanghua Gao, William A. Goddard Iii

Turkish Journal of Physics

Carbon has diverse structures, especially (0-dimensional) fullerenes, (1-dimensional) tubes have generated great interest among scientists and technologists. Studies of the structures and properties of these low dimensional carbon molecules show tremendous potential for use in nanoscale device applications. Motivated by these exciting possibilities in finding new forms of carbon materials and their potential applications, we have designed hypothetical single wall carbon nano-toroids. Carbon toroids are also ideal in studying the elastic and plastic deformation behavior of nanotubes under bending loads. We can accurately correlate the behavior of the tubes to its uniform curvature. In this particular work we focused on …


Pseudopotential-Based Full Zone K . P Technique For Indirect Bandgap Semiconductors: Si, Ge, Diamond And Sic, Ceyhun Bulutay Jan 2006

Pseudopotential-Based Full Zone K . P Technique For Indirect Bandgap Semiconductors: Si, Ge, Diamond And Sic, Ceyhun Bulutay

Turkish Journal of Physics

The k . p is a versatile technique that describes the semiconductor band structure in the vicinity of the bandgap. The technique can be extended to full Brillouin zone by including more coupled bands into consideration. For completeness, a detailed formulation is provided where the associated k . p parameters are extracted from the local empirical pseudopotential method in the form of band edge energies and generalized momentum matrix elements. We demonstrate the systematic improvement of the technique with the proper choice of the band edge states for the group-IV indirect bandgap semiconductors: Si, Ge, diamond and SiC of the …


Self-Diffusion Coefficients In Liquid Ag Using The Embedded Atom Model Based Effective Pair Potentials, Seyfetti̇n Dalgiç, Mutlu Çolakoğullari Jan 2006

Self-Diffusion Coefficients In Liquid Ag Using The Embedded Atom Model Based Effective Pair Potentials, Seyfetti̇n Dalgiç, Mutlu Çolakoğullari

Turkish Journal of Physics

We present the dynamical properties of liquid Ag at different temperatures, using the Mishin and Doyoma-Kagure version of the Embedded Atom Model (EAM) potentials. They have been evaluated within the framework of the mode-coupling theory, using a self-consistent scheme that uses as input data only the static structure functions and the interatomic pair potentials of the liquid Ag. We have computed single-particle and collective time dependent properties of liquid Ag, and thereby calculated its self-diffusion constants. We have also discussed our results comparing with both experimental data and results of molecular dynamic simulation.