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Determination Of H_{2}O_{2} Content Of Various Water Samples Using A Chemiluminescence Technique, Tuğba Tüğsüz, Elmas Gök, Serdar Ateş
Determination Of H_{2}O_{2} Content Of Various Water Samples Using A Chemiluminescence Technique, Tuğba Tüğsüz, Elmas Gök, Serdar Ateş
Turkish Journal of Chemistry
Hydrogen peroxide (H_{2}O_{2}) plays an important role in natural water samples. In this study H_{2}O_{2} concentrations were quantified in different water samples by chemiluminescence detection. This method was chosen because of its high sensitivity and suitability for determining low concentrations of H_{2}O_{2}. H_{2}O_{2} is introduced to the oxidation reaction of alkaline luminol solutions in the presence of Co^{2 + } ion catalyst. When these components are mixed, blue light (\lambda = 440 nm) is emitted. Maximum chemiluminescence intensity occurs within 2 s after mixing and is continuous for up to a few minutes, permitting accurate measurements at selected delay times. …
An Open Singularity-Free Cosmological Model With Inflation, Koray Karaca, Selçuk Bayin
An Open Singularity-Free Cosmological Model With Inflation, Koray Karaca, Selçuk Bayin
Turkish Journal of Physics
In the light of recent observations which point to an open universe (\Omega _{0} < 1), we reconsider singularity-free models, originally constructed for closed universes. Our model starts from a nonsingular state called prematter, governed by an inflationary equation of state P=( \gamma _{p}-1) \rho , where \gamma _{p} is a small positive parameter representing the initial vacuum dominance of the universe. Unlike the closed models, an open universe cannot be initially static hence, starts with an initial expansion rate represented by the initial value of the Hubble constant H(0). Therefore, our model is a two-parameter universe model (\gamma _{p},H(0)). During the prematter phase, due to the unusual characteristic of the equation of state, the universe heats up even though it expands. When the temperature in the universe reaches the Planck temperature T_{pl}, which is taken as the maximum attainable physical temperature, a first order phase transition carries the universe into the radiation era. Then the universe starts to behave as predicted in the standard model. The model proposed in this work predicts a value between 60 and 80 Km\cdot \sec ^{-1}\cdot Mpc^{-1} for the present value of the Hubble constant H_{0}, and the predicted value of \Omega _{0} lies between 0.3 and 0.6. Comparing the predictions of this model for the present properties of the universe with the recent observational results, we argue that the model constructed in this paper could be used as a realistic universe model.
Inflation In A Flat Universe, Koray Karaca, Selçuk Bayin
Inflation In A Flat Universe, Koray Karaca, Selçuk Bayin
Turkish Journal of Physics
We started the evolution of a flat universe from a nonsingular state called prematter which is governed by an inflationary equation of state P=(\gamma -1)\rho , where \gamma represents the initial vacuum dominance of the universe. The evolution of the universe-except in the prematter era-is affected neither by the initial vacuum dominance nor by the initial expansion rate of the universe. On the other hand, present properties of the universe, such as the Hubble constant, age and density, are sensitive to the value of the temperature at the decoupling ( T_{m}) . Over a range between 3\cdot 10^{4}and 5\cdot 10^{4} …
The Motion Of Cosmic Strings In The Schwarzschild Black Hole Spacetime, Sergey Roshchupkin, Yevgeniy Zinchenko
The Motion Of Cosmic Strings In The Schwarzschild Black Hole Spacetime, Sergey Roshchupkin, Yevgeniy Zinchenko
Turkish Journal of Physics
We study the classical dynamics of a bosonic string in the Schwarzschild spacetime using a perturbative scheme which is based on the assumption of a small value of a rescaled string tension parameter. The proposed approximation selfconsistently describes the string dynamics on the scale of large values for the worldsheet time in a fixed gauge.
Multiply Charged Ions Produced After Deexcitation Processes For Important Elements In Astrophysics, Adel M. El-Shime, Adel A. Ghoneim, Yehia A. Lotfy
Multiply Charged Ions Produced After Deexcitation Processes For Important Elements In Astrophysics, Adel M. El-Shime, Adel A. Ghoneim, Yehia A. Lotfy
Turkish Journal of Physics
Selection random number method (Monte Carlo technique) is used to calculate the ion charge state distributions (CSD) and mean ion charge \bar{q} after K-, L_{I}, L_{III}- and M_{I}- shell ionization in neutral atoms and their q-fold ground state ions (q = 0 to 10) from C to Fe elements. Atomic data for radiative and non-radiative transitions and electron shake off process, which is used in the modeling vacancy cascade program, are computed with relativistic wave functions. Use of atomic data is important to accurately model vacancy cascades. To enhance the agreement between calculated and experimental values, the electron shake-off processes …
Modeling Of Infrared Radiation For All Skies From Easy-To-Measure Meteorological Parameters At Tropical Location: Ilorin, Nigeria, Sunday O. Udo
Modeling Of Infrared Radiation For All Skies From Easy-To-Measure Meteorological Parameters At Tropical Location: Ilorin, Nigeria, Sunday O. Udo
Turkish Journal of Physics
Downward infrared radiation (L) and some easy-to-measure meteorological variables (relative humidity, clearness index and vapour pressure) were collected for a period of two years at Ilorin. Downward infrared radiation data were obtained using a pyrgeometer (Eppley-PIR), while data for relative humidity and vapour pressure for Ilorin were obtained from the Nigerian Meteorological Services, Lagos. Based on these data, using statistical regression analysis, empirical models (seven one-variable and nine two-variable) for predicting daily mean infrared radiation, from both clear and cloudy skies, were tested. Their advantage is that they only make use of easily measured meteorological parameters. The best one-variable model …
Operation Parameters Of The Thermionic Vacuum Arc Discharge, Tamer Akan
Operation Parameters Of The Thermionic Vacuum Arc Discharge, Tamer Akan
Turkish Journal of Physics
The thermionic vacuum arc (TVA) discharge with evaporating anodes employing directly heated thermionic cathodes is investigated. The TVA discharge generates a pure, gas-free metal vapor plasma containing ions with a directed energy. The TVA is strongly controlled by the cathodic electron beam and there is a quite good stability of important operation parameters like the arc voltage and the arc current.
Development Of Double Discharge Pulsed Electron Beam Generator And Its Preliminary Applications In Material Processing, Hi̇lal Göktaş, Gulay Oke, Mircea Udrea
Development Of Double Discharge Pulsed Electron Beam Generator And Its Preliminary Applications In Material Processing, Hi̇lal Göktaş, Gulay Oke, Mircea Udrea
Turkish Journal of Physics
This article presents the construction of a fast, intense electron beam generator, several of its operational properties and its preliminary applications. A fast filamentary discharge produced in a tube filled with Argon gas at pressure of about 0.1 torr. An electron beam is obtained with a current intensity of about 0.6 A for a 25 ns duration. The length of the filamentary discharge and the behavior of the beam in the magnetic field are examined. The interaction of the beam with different targets was investigated by Scanning Electron Microscope. It is also demonstrated that the device can be used to …
Timelike And Spacelike Ricci Collineation Vectors In String Fluid, Hüsnü Baysal, İhsan Yilmaz
Timelike And Spacelike Ricci Collineation Vectors In String Fluid, Hüsnü Baysal, İhsan Yilmaz
Turkish Journal of Physics
We study the consequences of the existence of timelike and spacelike Ricci collineation vectors (RCVs) for string fluid in the context of general relativity. Necessary and sufficient conditions are derived for a space-time with string fluid to admit a timelike RCV, parallel to u^a, and a spacelike RCV, parallel to n^a. In these cases, some results obtained are discussed.
Interaction Integrals Of Extended Bodies And Convolution/Folding Operation, Şule Kehnemi̇, R. Ömür Akyüz
Interaction Integrals Of Extended Bodies And Convolution/Folding Operation, Şule Kehnemi̇, R. Ömür Akyüz
Turkish Journal of Physics
The convolution, or folding, theorem related to Fourier transforms is applied to the evaluation of interaction integrals of certain extended bodies for the specific purpose of nuclear applications The integrals give analytical results for a class of functions when chosen from among uniform sharp and leptodermous spheres, delta-points, Yukawa, and Coulomb shapes. Such shapes are convenient to use as models for source density and point-point interaction.
Semi-Infinite Polarized Nuclear Matter With A Seyler-Blanchard Interaction, H. M. M. Mansour, Kh. A. Ramadan
Semi-Infinite Polarized Nuclear Matter With A Seyler-Blanchard Interaction, H. M. M. Mansour, Kh. A. Ramadan
Turkish Journal of Physics
The surface and curvature properties of semi-infinite polarized nuclear matter (SPNM) are calculated using a modified form of the Seyler-Blanchard potential. The level density parameter is extracted from the free energy using T^{2}-approximation. Good agreement is obtained between our calculations for the level density and other parameters which characterize the surface and curvature properties of SPNM and previous theoretical estimates. PACS number(s): 21.65.+f, 21.30.Fe
How Round Is Round? On Accuracy In Complex Dielectric Permittivity Calculations: A Finite-Size Scaling Approach, Eni̇s Tuncer
How Round Is Round? On Accuracy In Complex Dielectric Permittivity Calculations: A Finite-Size Scaling Approach, Eni̇s Tuncer
Turkish Journal of Physics
Accuracy in complex dielectric permittivity calculations in binary dielectric mixtures in two-dimensions are reported by taking into account the shape of the inclusion phase. The dielectric permittivity of the mixtures were calculated using the finite element method, and the permittivities were estimated by two different procedures. The results were compared with those of analytical models based on a mean field approximation and regular arrangement of disks. We have approached the problem emphasizing the finite-size behavior in which regular polygons with n sides were assumed to mimic the disk inclusion phase. It was found that at low concentrations, < 30%, decagon-approximated circles (n = 10) cause an error of < 0.1% in the effective medium quantities compared with results obtained using analytical models.
The Influence Of Ge Content And Annealing Temperature On The D.C And A.C Conductivity Of Ge_{X}Se_{1 - X} Thin Films, Maysoon Faisal Alias, M. N. Makadsi, Z. M. Al-Ajeli
The Influence Of Ge Content And Annealing Temperature On The D.C And A.C Conductivity Of Ge_{X}Se_{1 - X} Thin Films, Maysoon Faisal Alias, M. N. Makadsi, Z. M. Al-Ajeli
Turkish Journal of Physics
Various samples of Ge_{x}Se_{1 - x} system have been prepared for x = 0.05, 0.15& 0.25 in an evacuated quartz tube. Thin films of Ge_{x}Se_{1 - x} film have been prepared via a thermal evaporation method with 350 \pm 5 nm thickness and rate deposition 6 nm/s. The alloy structure and thin films have been examined by X-ray diffraction (XRD). Atomic absorption spectroscopy (AAS) was used to examine the concentration of the composite elements (Ge and Se). The d.c and a.c conductivity of Ge_{x}Se_{1 - x} thin film have been studied as a function of Ge content x and annealing …
Electrical Characteristics Of Si Doped With Sb By Laser Annealing, Raid A. Ismail, Aseel A. Hadi
Electrical Characteristics Of Si Doped With Sb By Laser Annealing, Raid A. Ismail, Aseel A. Hadi
Turkish Journal of Physics
Laser induced diffusion of antimony in silicon was obtained using a Nd:YAG pulsed laser. The irradiation of antimony-coated silicon by laser beam allowed melting and diffusion of antimony inside the silicon. Diodes were fabricated. Laser beam energy and substrate temperature played a major role in electrical sheet conductivity I-V, and C-V characteristics of the fabricated diodes. High laser energy reduced the electrical sheet conductivity and dominated the recombination current due to the generation-recombination process and trapping centers. On the other hand, the diffusion current dominated for diodes fabricated under heating conditions of the sample during laser irradiation. The C-V measurements …
Microwave Signal Attenuation In Harmattan Weather Along Calabar-Akampkpa Line-Of-Sight Link, O. E. Eyo, A. I. Menkiti, Sunday O. Udo
Microwave Signal Attenuation In Harmattan Weather Along Calabar-Akampkpa Line-Of-Sight Link, O. E. Eyo, A. I. Menkiti, Sunday O. Udo
Turkish Journal of Physics
Line-of-sight (LOS) attenuation at 6.44GHz was measured at Calabar (4° 58' N, 8° 17' E) for ten months (Aug '93-May '94) using the Nigerian Telecommunications radio signal. The measurement was made with the intent of highlighting microwave signal attenuation in Harmattan weather conditions. The results are presented in terms of mean signal level and fog attenuation, fade rate distribution, fade depth distribution and scintillation index. The observed attenuation values due to Harmattan (fog) and the calculated (using Altshuler's model) are in fairly good agreement. Also, the statistics of fade distribution show fast fading of longer duration of the order of …
Relationship Between Global Solar Radiation And Sunshine Duration For Onne, Nigeria, Louis E. Akpabio, Sunday E. Etuk
Relationship Between Global Solar Radiation And Sunshine Duration For Onne, Nigeria, Louis E. Akpabio, Sunday E. Etuk
Turkish Journal of Physics
Measurements of global solar radiation and sunshine duration data during the period from 1984 to 1999 at Onne (within the rainforest climatic zone of southern Nigeria) were used to establish an Angstrom-type correlation equation. Five other commonly used correlations between global solar radiation and sunshine duration were also used to estimate global solar irradiation for Onne and their results are compared with our model. A good agreement (greater than 90% in most cases) was observed between the measured and the predicted values of our model.
Initial Electron Beam Polarization Measurement In E-\Gamma Collisions, Gökhan Ünel
Initial Electron Beam Polarization Measurement In E-\Gamma Collisions, Gökhan Ünel
Turkish Journal of Physics
The future high energy e e colliders, together with the complementary \gamma \gamma option, will offer possibilities for both discovery and precision physics. The uncertainty on the initial beam polarizations contributes to the systematic errors in each case. Therefore, it is crucial to obtain the precise beam polarizations by independent measurements. The e \gamma \rightarrow \nu W process in the e \gamma mode can be used to experimentally determine the polarization of the initial e beam. This note addresses the feasibility of making such a measurement with a relative statistical error of one percent. Generator and detector level MC tools …
Fourth Sm Family Manifestations At Clic, R. Çi̇ftçi̇, A. K. Çi̇ftçi̇, Erdal Recepoğlu, Saleh Sultansoy
Fourth Sm Family Manifestations At Clic, R. Çi̇ftçi̇, A. K. Çi̇ftçi̇, Erdal Recepoğlu, Saleh Sultansoy
Turkish Journal of Physics
The latest electroweak precision data allow the existence of additional chiral generations in the standard model. We study prospects of search for the fourth standard model family fermions and quarkonia at e^{+}e^{-} and \gamma \gamma options of CLIC. It is shown that CLIC will be powerfull machine for discovery and investigation of both fourth family leptons and quarkonia. Moreover, the formation of the fourth family quarkonia will give a new opportunity to investigate Higgs boson properties.
Nuclear Matrix Elements Of Double Beta Decay In Deformed Nuclei, C. Selam, Atalay Küçükbursa, H. Bi̇rcan, H. A. Aygör, T. Babacan, İ. Maraş, A. Kökçe
Nuclear Matrix Elements Of Double Beta Decay In Deformed Nuclei, C. Selam, Atalay Küçükbursa, H. Bi̇rcan, H. A. Aygör, T. Babacan, İ. Maraş, A. Kökçe
Turkish Journal of Physics
Nuclear matrix elements (M_{GT}) for two-neutrino double beta transitions of selected nuclei were calculated via a QRPA approach by considering the charge-exchange spin-spin interactions in the particle-hole channel among nucleons. Calculations were performed for both spherical and deformed cases of nuclei. As a result of these calculations, it has been seen that, although the value of the nuclear matrix elements in deformation case are 2-4 times smaller when compared with that of the spherical case, it is still 2-8 times greater than the experimental values.
Clebsch-Gordan Equalities That Imply The Vanishing Of Particular 6j Symbols, Harry A. Mavromatis
Clebsch-Gordan Equalities That Imply The Vanishing Of Particular 6j Symbols, Harry A. Mavromatis
Turkish Journal of Physics
Three Clebsch-Gordan equalities and three individual Clebsh-Gordan relations are obtained by studying the non-accidental vanishing of certain 6j symbols.
Characterization Of In_{4}Te_{3} Single Crystals, M. Dongol, M. M. Nassary, M. K. Gerges, M. A. Sebag
Characterization Of In_{4}Te_{3} Single Crystals, M. Dongol, M. M. Nassary, M. K. Gerges, M. A. Sebag
Turkish Journal of Physics
Single crystals of In_{4}Te_{3} grown by modified Bridgman technique were characterized by measurement of the Hall coefficient, electrical conductivity and Seebeck coefficient, in the temperature range 200-500 K. The investigated sample was found to be of P-type conductivity.R_{H} at room temperature was 3.1 \times 10^{14} cm^{3}/coul and the carrier concentration was evaluated as 2.007 \times 10^{14} cm^{3}. Energy gap \Delta E_{g} and ionization energy \Delta E_{a} were estimated as 0.28 eV and 0.12 eV, respectively, and the diffusion coefficient, the diffusion length, the mean free time between collision and the effective mass of carriers were evaluated. The variation of the …
Variation In Thickness Of Copper Films Deposited At Various Distances And Angles Using The Thermionic Vacuum Arc, Tamer Akan, Naci̇ Ekem
Variation In Thickness Of Copper Films Deposited At Various Distances And Angles Using The Thermionic Vacuum Arc, Tamer Akan, Naci̇ Ekem
Turkish Journal of Physics
The thermionic vacuum arc (TVA) is a new technique for the deposition of thin metallic films. Copper depositions were made on glass substrates placed at various distances and angles with respect to the TVA source. By measuring the thickness of the film on each substrate, the variation in the thickness as a function of the distance and angle with respect to the TVA source is investigated.
Study Of The Structure And Some Physical Properties Of Sodium-Boro-Phosphate Glasses Containing Antimony And Iron Oxides, Karam Abdel-Aati̇ Ali, Ahmet Gamal El-Din Mostafa
Study Of The Structure And Some Physical Properties Of Sodium-Boro-Phosphate Glasses Containing Antimony And Iron Oxides, Karam Abdel-Aati̇ Ali, Ahmet Gamal El-Din Mostafa
Turkish Journal of Physics
Boro-phosphate glasses containing transition metal oxides are of special interest. Hence, some sodium-Boro-phosphate glasses containing iron and antimony oxides were prepared and investigated. The structural investigation indicated the presence of different borate groups as well as tetragonal phosphate units. Most of the iron cations were found to occupy the low spin Fe^{3 +} in the tetrahedral coordination state. It was observed that some antimony act as network former cations and some others act as bridges between any two adjacent polyhedra. At high antimony oxide content, the formation of some Sb-Fe bonds was also detected. The magnetic susceptibility measurements showed a …
Extragalactic Objects In Basle Fields, Selçuk Bi̇li̇r, Yüksel Karataş, Serap Ak
Extragalactic Objects In Basle Fields, Selçuk Bi̇li̇r, Yüksel Karataş, Serap Ak
Turkish Journal of Physics
We discriminated between the extragalactic objects (galaxies and quasars) and stars for Basle star fields, Plaut I, SA 54, and SA 82 by comparing Basle fields and APS POSS I finder charts. Their numbers are 187, 70, and 93 for Plaut I, SA 54, and SA 82, respectively. Most of these objects are apparently faint in V, and they cause an overestimated local luminosity function for absolutely faint magnitudes, M(V) > 5. This effect is more conspicious for the field Plaut I.
Microwave Rotational Components Of The \Nu_9= 1 And \Nu _{10} = 2 Vibrational Modes Of ^{13}Ch_{3}Cch Molecule In The Range 16 -- 50 Ghz, Mohammad Al-Share, J. A. Roberts
Microwave Rotational Components Of The \Nu_9= 1 And \Nu _{10} = 2 Vibrational Modes Of ^{13}Ch_{3}Cch Molecule In The Range 16 -- 50 Ghz, Mohammad Al-Share, J. A. Roberts
Turkish Journal of Physics
Some rotational components have been measured in the ground, the \nu _9 = 1 and the \nu _{10} = 2 vibrational states for ^{13}CH_3CCH isotopic species in the frequency range 16--50 GHz. A set of rotational constants has been determined, which gives the best fit between the observed and the calculated frequencies, for each vibrational state. A Fermi resonance was found between these two states.
Studies On Some Lithium-Borate Glasses Containing Iron And Copper, G. A. Yahya
Studies On Some Lithium-Borate Glasses Containing Iron And Copper, G. A. Yahya
Turkish Journal of Physics
A lithium-borate-glass system containing iron and copper cations has been thoroughly investigated, in order to obtain information about the structural role of both the iron and copper in such glass hosts. The amorphous phase of the prepared glass samples was confirmed from their X-ray diffraction. From the infrared spectra it was concluded that the glass networks are highly deformed and boron appeared in both tri- and tetra-hedral coordination states as well as in some ring structure. As copper was introduced, replacing lithium, it acts as a network modifier only while the iron acts as network former (FeO_4). The molar magnetic …
Esr Studies Of A Quartz Single Crystal From The Menderes Massif-Turkey, Ülkü Ulusoy
Esr Studies Of A Quartz Single Crystal From The Menderes Massif-Turkey, Ülkü Ulusoy
Turkish Journal of Physics
In a recent work, quartz single crystal extracted from the pegmatitic vein in the Menderes Massif (Western Turkey) was investigated and the most recent geological events of the sample was dated using Al centers by ESR (electron spin resonance) techniques. The estimated age of 1.8 \pm 0.5 My agree with neither the previous age evaluated to be 12 My by using isotopic dating techniques nor the lifetimes of these centers in the sample. It was suggested that the thermal or geothermal stressing history of the metamorphic region must have changed the apparent ESR age several cycles in this period. The …