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Full-Text Articles in Physical Sciences and Mathematics

Molecular Dynamics Simulations Of Super Heated Ni_4 Cluster, M. Haluk Güven Jan 2000

Molecular Dynamics Simulations Of Super Heated Ni_4 Cluster, M. Haluk Güven

Turkish Journal of Physics

The fragmentation mechanism of the super heated Ni4 cluster is studied by employing the microcanonical molecular dynamics simulations and an empirical model potential. Ni$_{4}$ cluster is heated up above the bulk Ni evaporation point temperature and then classical trajectory analysis as well as RRK theory are used to calculate survival probability, evaporation rate, average kinetic energy release and dissociation energy.


Characterization Of Phenanthrene Single Crystals, M. Tariq Bhatti, Anwar Manzoor Rana, Mazhar Ali, Gul N. Shahid, M. Saleh Jan 2000

Characterization Of Phenanthrene Single Crystals, M. Tariq Bhatti, Anwar Manzoor Rana, Mazhar Ali, Gul N. Shahid, M. Saleh

Turkish Journal of Physics

Single crystals of phenanthrene were successfully grown from melt using Bridgeman Crystal Growth System Type 365. The starting material was purified by sublimation and zone refining techniques in specially designed crystal growth tubes. Phenanthrene single crystals grow with the plane of maximum growth corresponding to the ab-crystallographic plane, and cleave readily in this plane. The optical absorption spectra of phenanthrene single crystals and phenanthrene crystals dissolved in benzene, alcohol and acetone solutions were studied in the wavelength range (200 - 400 nm). The optical excitations i.e., \( \pi - \pi^{*} \) transitions, are attributed to the weak and strong optical …


Antiferromagnetic Transition In \Alpha-Mn-Fe System, R. K. Nkum, F. Boakye Jan 2000

Antiferromagnetic Transition In \Alpha-Mn-Fe System, R. K. Nkum, F. Boakye

Turkish Journal of Physics

Antiferromagnetic transition in $\alpha$-Mn-Fe alloys has been studied using resistivity-temperature measurements from 300 to 1.5 K. The results indicate that the transition temperature $T_N$ of the samples studied increases with increasing Fe concentration. This suggests that the N\'{e}el temperature is affected by Fe. Also, Fe plays a significant role in the local disorder on the magnetic moment of the ions in the complex manganese structure.


Radioluminescent Properties Of Cds(Ag) Crystals, Ruhi̇ Kaplan, F. Esen Özsan Jan 2000

Radioluminescent Properties Of Cds(Ag) Crystals, Ruhi̇ Kaplan, F. Esen Özsan

Turkish Journal of Physics

The radioluminescent proporties of silver-doped cadmium sulphide, CdS(Ag), crystals excited by 5.5 MeV $ \alpha $-particles from an $ ^{241}$Am radioactive source have been investigated. The emission spectra, decay profiles and thermal quenching curves were obtained accurately at temperatures between 80 K and 300 K. Two main radioluminescent emission bands centered at about 5760 \AA\ and 5940 \AA\ were observed. Their decay curves were found to be fast and nonexponential. From the thermal quenching of radioluminescence, the activation energies of centers responsible for these emissions were determined. The results are interpreted as the radioluminescence is possibly due to donor-acceptor pair …


Synthesis And Characteristics Of Nickel Manganite By Lithiation, S. V. Salvi, M. R. Parab Jan 2000

Synthesis And Characteristics Of Nickel Manganite By Lithiation, S. V. Salvi, M. R. Parab

Turkish Journal of Physics

Spinel nickel manganite has been synthesized using ceramic technique, from (2MnO$_{2}$+NiO) mixture reduced using LiAlH$_{4}$. Powder X-ray diffractometry (XRD) indicates the formation of cubic spinel (a=8.33 A^o), while IR absorption spectral features are rather broad, though similar to those of spinel. The d.c. electrical conductivity of the ceramic is much smaller than that reported for NiMn$_{2}$O$_{4}$. Even though the band gap remains the same, when the sintering temperature is increased from 950^oC to 1100 ^oC, all other changes are insignificant except that the porosity and particle size nearly halve. The characteristics of the system are discussed in terms of `lithiation'.


K-Vacancy Production In The Collision Of Highly Charged Relativistic Ions With Heavy Atoms, P. K. Khabibullaev, V. I. Matveev, D. U. Matrasulov Jan 2000

K-Vacancy Production In The Collision Of Highly Charged Relativistic Ions With Heavy Atoms, P. K. Khabibullaev, V. I. Matveev, D. U. Matrasulov

Turkish Journal of Physics

A general expression for the cross section of the inelastic collision of relativistic highly charged ion with heavy (relativistic) atoms is obtained using the generalized eikonal approximation. In the ultrarelativistic limit, the obtained formula coincides with a known exact one. As an application of the obtained result, probability and cross section of the K-vacany production in the $U^{92+} - U^{91+}$ collision are calculated.


Crystallographic Analysis Of Martensitic Transformation In Cusn Alloy, Ekrem Artunç, Seyfetti̇n Çakmak, Seval Çakmak Jan 2000

Crystallographic Analysis Of Martensitic Transformation In Cusn Alloy, Ekrem Artunç, Seyfetti̇n Çakmak, Seval Çakmak

Turkish Journal of Physics

In this study, the Kajiwara model has been applied to Cu-14.8at.\%Sn alloy with good agreement with experimental results. For this alloy, the austenite phase has a body centered cubic (bcc) lattice and the martensite phase has a monoclinic 9R superlattice. Using the lattice parameters of both phases, the calculated habit plane indices, magnitude of the lattice invariant shear and orientation relationships, have been compared with the observed results for this alloy.


Devitrification Of Volcanic Glasses In Konya Volcanic Units, Turkey, Zehra Karakaş, Selahatti̇n Kadi̇r Jan 2000

Devitrification Of Volcanic Glasses In Konya Volcanic Units, Turkey, Zehra Karakaş, Selahatti̇n Kadi̇r

Turkish Journal of Earth Sciences

The study area is composed of volcanic, sedimentary and volcano-sedimentary units, which are exposed south and southwest of the city of Konya. XRD analysis indicates that the volcanic units contain halloysite, kaolinite, smectite, illite and sepiolite type clay minerals and opal-CT, feldspar, quartz, minamiite and jarosite type non-clay minerals. SEM studies show that volcanic glasses, which are the main component of the volcanic units, appeared as curviplanar, vesicular-planar and in highly fractured shapes. Fractures and dissolution voids of the volcanic glasses are generally filled by hexagonal kaolinite, fibrous halloysite and smectite. Mineralogical and micromorphological observations indicate that clay minerals were …


Geochemistry And Significance Of Mafic Dyke Swarms In The Pozantı-Karsantı Ophiolite (Southern Turkey), Osman Parlak Jan 2000

Geochemistry And Significance Of Mafic Dyke Swarms In The Pozantı-Karsantı Ophiolite (Southern Turkey), Osman Parlak

Turkish Journal of Earth Sciences

The Pozantı-Karsantı ophiolite, which is one of a number of the Late Cretaceous oceanic lithospheric remnants in southern Turkey, is situated in the eastern Tauride belt and consists of three distinct thrust sheets: an ophiolitic melange, a metamorphic sole, and an ophiolitic stratigraphic sequence. These units (except the ophiolitic melange) are intruded by isolated microgabbro-diabase dykes at all structural levels. The dykes from the lower crustal rocks (cumulates) are subalkaline in character and chemically similar to island arc tholeiitic basalts and basaltic andesites. They are enriched in some LIL elements (Rb, Ba, K and Sr) and depleted in HFS elements …


Late Devonian Conodont Fauna Of The Gümüşali Formation, The Eastern Taurides, Turke, Şenol Çapkinoğlu, İsmet Gedi̇k Jan 2000

Late Devonian Conodont Fauna Of The Gümüşali Formation, The Eastern Taurides, Turke, Şenol Çapkinoğlu, İsmet Gedi̇k

Turkish Journal of Earth Sciences

The Late Devonian Gümüşali formation of the eastern Taurides is a terrigenous-carbonate rock sequence about 600 m thick, consisting mainly of quartz sandstone, quartz siltstone, shale, and carbonate rocks. Palaeontologic and sedimentologic data mainly indicate a shallow subtidal depositional environment. This sequence generally represents the shallow-water polygnathid-icriodid biofacies, and contains conodont faunas that range from the Upper falsiovalis Zone into the Upper praesulcata Zone. However, they do not correlate well to the Late Devonian standard conodont zonation because of the lack of zonally diagnostic species and the irregular vertical distributions of the present taxa. Herein, 54 taxa belonging to nine …


Late Devonian (Famennian) Conodonts From Denizliköyü, Gebze, Kocaeli, Northwestern Turkey, Şenol Çapkinoğlu Jan 2000

Late Devonian (Famennian) Conodonts From Denizliköyü, Gebze, Kocaeli, Northwestern Turkey, Şenol Çapkinoğlu

Turkish Journal of Earth Sciences

Late Devonian (Famennian) conodont faunas have been described from two incomplete stratigraphic sections (GD and GB) of the Ayineburnu member of the Tuzla formation, Denizliköyü, Gebze, Kocaeli, northwestern Turkey. The section GD comprises the Lower and Middle expansa Zones, and the section GB contains the Middle and Upper expansa Zones. Zonal indices for the Middle expansa Zone are identified in the section GB, whereas this zone is recognized on the basis of other key taxa in the section GD. Also, a new species of the Genus Branmehla, Branmehla gediki n.sp. is described from the section GD.


On Generalized Higher Derivations, Atsushi Nakajima Jan 2000

On Generalized Higher Derivations, Atsushi Nakajima

Turkish Journal of Mathematics

We define the notion of generalized higher derivations and give some elementary relations between generalized higher derivations and higher derivations in the usual sense. We extend the result of an exact sequence of the set of all derivations $\text{Der}(A, M)$ and the set of all generalized derivations $g\text{Der}(A, M)$ given in [N1, Theorem 2.4]. Moreover, we discuss generalized higher Jordan derivations and Lie derivations.


Multipliers Between Orlicz Sequence Spaces, P. B. Djakov, M. S. Ramanuan Jan 2000

Multipliers Between Orlicz Sequence Spaces, P. B. Djakov, M. S. Ramanuan

Turkish Journal of Mathematics

Let $M, N $ be Orlicz functions, and let $D(\ell_M , \ell_N ) $ be the space of all diagonal operators (that is multipliers) acting between the Orlicz sequence spaces $\ell_M$ and $\ell_N$. We prove that the space of multipliers $D(\ell_M , \ell_N )$ coincides with (and is isomorphic to) the Orlicz sequence space $ \ell_{M_N^{*}} ,$ where $ M_N^{*} $ is the Orlicz function defined by $M_N^{*}(\lambda ) = \sup \{ N(\lambda x) - M(x), \; x \in (0,1) \}$.


Conjugacy Structure Type And Degree Structure Type In Finite P-Groups, Yadalah Marefat Jan 2000

Conjugacy Structure Type And Degree Structure Type In Finite P-Groups, Yadalah Marefat

Turkish Journal of Mathematics

Let $G$ be a finite $p-$group, and denote by $k(G)$ number of conjugacy classes in $G$. The aim of this paper is to introduce the conjugacy structure type and degree structure type for $p-$groups, and determine these parameters for $p-$groups of order $p^5$, and calculate $k(G)$ for them.


New And Old Types Of Homogeneity, Ali̇ Ahmad Fora Jan 2000

New And Old Types Of Homogeneity, Ali̇ Ahmad Fora

Turkish Journal of Mathematics

We introduce new types of homogeneity ; namely : locally homogeneity and closed homogeneity .Several results are included discussing some relations between these types and the old ones. Some characterization and decomposition theorems are obtained. Relevant examples and counterexamples are discussed throughout this paper.


The P-Stirling Numbers, Russel Merris Jan 2000

The P-Stirling Numbers, Russel Merris

Turkish Journal of Mathematics

The purpose of this article is to introduce \( p \)-Stirling numbers of the first and second kinds.


Some Radius Problem For Certain Families Of Analytic Functions, Yaşar Polatoğlu, Meti̇n Bolcal Jan 2000

Some Radius Problem For Certain Families Of Analytic Functions, Yaşar Polatoğlu, Meti̇n Bolcal

Turkish Journal of Mathematics

The aim of this paper is to give bounds of the radius of $\alpha $-convexity for certain families of analytic functions in the unit disc. The radius of $\alpha $-convexity is generalization of the radius of convexity and the radius of starlikeness, and introduced by S.S.Miller; P.T.Mocanu and M.O.Reade [3,4]


A Special Quasi-Linear Mapping And Its Degree, Aki̇f Abbasov Jan 2000

A Special Quasi-Linear Mapping And Its Degree, Aki̇f Abbasov

Turkish Journal of Mathematics

In this article, for the purpose of expanding to the mappings between Banach manifolds, a degree is determined in for the mappings between Banach spaces, which are from the obvious class.


Applications Of The Tachibana Operator On Problems Of Lifts, Abdullah Mağden, Ekrem Kadioğlu, Ari̇f A. Salimov Jan 2000

Applications Of The Tachibana Operator On Problems Of Lifts, Abdullah Mağden, Ekrem Kadioğlu, Ari̇f A. Salimov

Turkish Journal of Mathematics

The purpose of the present paper is to study, using the Tachibana operator, the complete lifts of affinor structures along a pure cross-section of the tensor bundle and to investigate their transfers. The results obtained are to some extent similar to results previously established for tangent (cotangent) bundles \lbrack 1\rbrack. However there are various important differences and it appears that the problem of lifting affinor structures to the tensor bundle on the pure cross-section presents difficulties which are not encountered in the case of the tangent (cotangent) bundle.


On Non-Homogeneous Riemann Boundary Value Problem, Kadi̇r Kutlu Jan 2000

On Non-Homogeneous Riemann Boundary Value Problem, Kadi̇r Kutlu

Turkish Journal of Mathematics

In this paper we consider non-homogeneous Riemann boundary value problem with unbounded oscillating coefficients on a class of open rectifiable Jordan curve.


Lifts Of Derivations To The Semitangent Bundle, Ari̇f A. Salimov, Ekrem Kadioğlu Jan 2000

Lifts Of Derivations To The Semitangent Bundle, Ari̇f A. Salimov, Ekrem Kadioğlu

Turkish Journal of Mathematics

The main purpose of this paper is to investigate the complete lifts of derivations for semitangent bundle and to discuss relations between these and lifts already known.


Strongly Prime Ideals In Cs-Rings, Gonca Güngöroğlu Jan 2000

Strongly Prime Ideals In Cs-Rings, Gonca Güngöroğlu

Turkish Journal of Mathematics

We study and characterize strongly prime right ideals in CS-rings.


On Torsion-Free Barely Transitive Groups, Mahmut Kuzucuoğlu Jan 2000

On Torsion-Free Barely Transitive Groups, Mahmut Kuzucuoğlu

Turkish Journal of Mathematics

B. Hartley asked the following question: Does there exist a torsion free barely transitive group? Existence of torsion free simple barely transitive group is also unknown. We answer the latter question negatively in a special case. Moreover we proved the following: Let $G$ be a simple barely transitive group, and $H$ be a stabilizer of a point. If for a non-identity element $x \in G$, $C_G (x)$ is infinite then, $C_G (x)$ cannot contain $H$.


An Extended Adiabatic Approach For Nuclear Reactions, Mustafa Yilmaz, Bülent Gönül Jan 2000

An Extended Adiabatic Approach For Nuclear Reactions, Mustafa Yilmaz, Bülent Gönül

Turkish Journal of Physics

In this letter, an alternative approximation is developed for the treatment of breakup process in nuclear reactions, which presents a way of evaluating non-adiabatic corrections to the adiabatic model three-body wavefunction by introducing a more consistent prescription for the continuum n-p center of mass energy. Although the present formalism goes beyond the quasi-adiabatic approach, due to the use of exact continuum channel energies, its application to deuteron involving reactions at medium energies shows that such an approach can not be used in its present form. A possible reason behind this failure is discussed.


Temperature Dependence Of Vickers Microhardness And Creep Study Of In_X Bi_{2-X} Te_3 Crystals, G. R. Pandya, S. R. Bhavsar, C. F. Desai Jan 2000

Temperature Dependence Of Vickers Microhardness And Creep Study Of In_X Bi_{2-X} Te_3 Crystals, G. R. Pandya, S. R. Bhavsar, C. F. Desai

Turkish Journal of Physics

Temperature dependence of Vickers microhardness of ln$_x$ Bi$_{2-x}$ Te$_3$ single crystals with x ranging from 0.1 to 0.5 has been studied. Loading time dependence of microhardness at different temperatures has been used for creep study in the temperature range 300 K to 400 K. The activation energy for indentation creep of the crystals has been evaluated.


The Growth Of P-Type A^{Iii} B^{Iii} C_2^{V I} Single Crystals, Beki̇r Gürbulak, Cevdet Coşkun, Seydi̇ Doğan, Aytunç Ateş, Yahya Kemal Yoğurtçu Jan 2000

The Growth Of P-Type A^{Iii} B^{Iii} C_2^{V I} Single Crystals, Beki̇r Gürbulak, Cevdet Coşkun, Seydi̇ Doğan, Aytunç Ateş, Yahya Kemal Yoğurtçu

Turkish Journal of Physics

$A^{III}B^{III}C_2^{VI}$ single crystals were grown by the modified Bridgman-Stockbarger method, a procedure similar to direct freezing in our crystal growth laboratory. $A^{III}B^{III}C_2^{VI}$ compounds are collected into two groups (III. group: TI, Ga, In and VI. group: Se, S, Te): 1. TlGaSe$_2$, TlGaS$_2$ and TlInS$_2$ have layer structure. 2. TlInSe$_2$, TlInTe$_2$ and TlGaTe$_2$ have chained structure. The main reasons such crystals grown with this method is similar to the direct freezing method because 1) quality of crystals is the same as crystals grown by other methods, and 2) growth time of crystals is shorter by about 5-10 days. None of the …


Solar Observations Made At The Malatya Station With Danjon Astrolabe, Orhan Gölbaşi, Hüseyi̇n Kiliç, Fernand Chollet Jan 2000

Solar Observations Made At The Malatya Station With Danjon Astrolabe, Orhan Gölbaşi, Hüseyi̇n Kiliç, Fernand Chollet

Turkish Journal of Physics

The first results of astrometric solar observations made at the Malatya Station with a modified version of the Paris Observatory astrolabe are presented. This campaign was conducted as part of a cooperation between Inonü University and the Paris Observatory. The astrolabe, exactly the same as the one at Santiago de Chile [1], uses two reflecting prisms instead of transparent prisms in order to be able to observe at two zenith distances of 30^o and 60^o. The time is supplied by a Global Positioning System (GPS) receiver. The measurements (Table 1, 2) made between 1993 and 1994, were used in obtaining …


Thickness Dependence Of C/A Polytwin Structures Observed In Epitaxial Oxide Ferroelectric Thin Films, S. Pami̇r Alpay, Alexander L. Roytburd Jan 2000

Thickness Dependence Of C/A Polytwin Structures Observed In Epitaxial Oxide Ferroelectric Thin Films, S. Pami̇r Alpay, Alexander L. Roytburd

Turkish Journal of Physics

Ferroelectric or ferroelastic epitaxial films undergoing a cubic-to-tetragonal phase transformation usually relax the resultant strain energy due to lattice misfit by forming a polytwin (polydomain) structure. Polydomain formation occurs at the expense of building interdomain interfaces and microstresses which develop at the film-substrate interface due to the periodic deviation of the strain. The interplay between these components results in a critical thickness for domain formation below which the polydomain structure is not stable. In this article, we investigate the film thickness dependence of a polydomain structure using a thermodynamical approach.


The Effect Of Iterative Solutions In The Quasi-Adiabatic Treatment Of Transfer Reactions Involving Deuterons, Mustafa Yilmaz, Bülent Gönül Jan 2000

The Effect Of Iterative Solutions In The Quasi-Adiabatic Treatment Of Transfer Reactions Involving Deuterons, Mustafa Yilmaz, Bülent Gönül

Turkish Journal of Physics

Using an iterative scheme, the effects of a more correct treatment of large n-p components of deuteron channel wavefunction in the continuum, which are associated with near-side contributions of transition amplitude, are investigated in the framework of the reformulated quasi-adiabatic model for the \( ^{116} \)Sn \( (d,p) \) \( ^{117} \)Sn reaction at 79 MeV bombarding energy. As the \( \ell_{n} \)-transfer rises, the far-side amplitude increases with improvements in the linear and angular momentum responce, which results in a relative suppression of the near-side components of the amplitude. Therefore, one might expect that the iteration of the quasi-adiabatic …


The Lattice Dynamics Of Bcc Titanium, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇ Jan 2000

The Lattice Dynamics Of Bcc Titanium, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇

Turkish Journal of Physics

Using in measurements of the phonon frequencies of bcc Titanium, the lattice dynamical calculations are performed on the same phase by using the Third-neighbour Clark-Gazis-Wallis(CGW) model. The theory is used to compute the phonon dispersion curves, the frequency spectra and the lattice spesific heat of the studied phase. The obtained results are compared with the available experimental data.