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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.

Microhardness Creep In Single Crystals Of Tin-Chalcogenides, S. M. Vyas, C. F. Desai, R. C. Shah, G. R. Pandya

Turkish Journal of Physics

SnSe and SnS have been grown by Bridgman- Stockbarger method. Loading time as a function of vickers microhardness has been measured at different temperatures in the range 303 K to 388K. Al measurement of hardness have been carried out on the cleavage planes. The activation energy for creep has been evaluated to be 2.92 and 1.75 K Cal/mole, respectively, for SnSe and SnS crystals.

Doping Of High-Temperature Superconductors, Sh. Meretliev, K. B. Sadykov, A. Berkeliev

Turkish Journal of Physics

High-temperature superconducting ceramics systems YBaCuO and BiSrCaCuO, both doped by Pb, Sb, Li, K, Na and non-doped, have been produced by the method of solid phase reaction synthesis. The principle of controlled valency by Vervey has been used to characterize high-temperature superconductors. High-temperature superconducting ceramics have been obtained with properties stable in time by single-purpose doping.

The Absorption Properties Of P-Type Tlin_X Ga_{(1-X)} Se_2 And Tlgase_2, Beki̇r Gürbulak, Muhammet Yildirim, Aytunç Ateş, Sebahatti̇n Tüzemen, Yahya Kemal Yoğurtçu

Turkish Journal of Physics

$p-TlGaSe_2$, $p-TlIn_{0.3}Ga_{0.7}Se_2$ and $p-TlIn_{0.5}Ga_{0.5}Se_2$ single crystals were grown by the modified Bridgman-Stockbarger method in our crystal growth laboratory. The absorption measurements were carried out on $p-TlIn_xGa_{(1-x)}Se_2$ samples in temperature range 10-300 K in steps of 10 K. The binding energies of $p-TlGaSe_2$, $p-TlIn_{0.3}Ga_{0.7}Se_2$ and $p-TlIn_{0.5} Ga_{0.5}$ $Se_2$ were obtained as \\ 35.0 meV, 16.5 meV and 14.5 meV, respectively. THe direct band gaps were calculated as 2.244 eV, 2.195 eV, 2.164 eV in $p-TlGaSe_2$, 2.158 eV, 2.131 eV, 2.098 eV in $p-TlIn_{0.3}Ga_{0.7}Se_2$, and 2.107 eV, 2.075 eV, 2.019 eV in $p-TlIn_{0.5}Ga_{0.5}Se_2$ respectively, at sample temperatures of 10 K, 140 K …

Chemically Synthesised Cd_{(1-X)}Zn_Xse Thin Films: Spectro-Structural And Microscopic Studies, D. S. Sutrave, G. S. Shahane, V. B. Patil, L. P. Deshmukh

Turkish Journal of Physics

This paper presents information pertaining to the chemo-mechanical synthesis of (Cd,Zn) Se thin films with a variable composition which has been brought about with the objective to study deposition history and growth kinetics, as well as structural changes and the optical properties. The effect of various process parameters, such as deposition time and temperature, concentration of species, speed of the substrate rotation, pH etc., on the growth and quality of the films is studied experimentally. At first sight, mechanistic interpretation of the reaction mechanism is given based on the influence of the process parameters on the film growth and the …

Welcoming Address: "Mathematical Concepts In Politics", Erdal İnönü

Turkish Journal of Physics

No abstract provided.

Generalized 2d Yang-Mills Theories: Large-N Limit And Phase Structure, Masoud Alimohammadi

Turkish Journal of Physics

After review the 2D Yang--Mills theories (YM$_2$) and its large--$N$ behaviour, the Generalized 2D Yang--Mills theories (gYM$_2$) and their partition functions on a general two--dimensional Riemann surface are discussed.The large--$N$ behaviour of these models is studied in weak regime, and in strong regime, we restrict ourselves to $\phi^4$ gYM$_2$. We show that this model has a third order phase transition, similar to ordinary YM$_2$ theory.

Global Results In Space Of Inter-Monomer Interactions For Hp Lattice Model, M. R. Ejtehadi̇, V. Shahrezaei̇, N. Hamedani̇

Turkish Journal of Physics

Using the ground state candidates for Hydrophobic-Polar lattice model on a two dimensional square lattice, we exactly enumerate the native states of proteins with length up to 20 for a wide range of energy parameters. We find the reduced set of contact maps, ground state candidates, perfectly stable sequences and designability of configurations.

The Statistics Of Energy States Of A Hookean Model For Proteins, Ayşe Erzan, Erkan Tüzel

Turkish Journal of Physics

A generic model of a random polypeptide chain, with discrete torsional degrees of freedom and Hookean springs connecting pairs of hydrophobic residues, reproduces the energy probability distribution of real proteins over a very large range of energies. We show that this system with harmonic interactions, under dissipative dynamics driven by random noise, leads to a distribution of energy states obeying a modified one-dimensional Ornstein-Uhlenbeck process with reflecting boundary conditions, and giving rise to distributions of the Wigner or inverse Gaussian form. A continuum approximation leads to a path integral formulation of the problem. PACS 5.65+b,5.70Ln,87.17.Aa

Multi-Species Asymmetric Exclusion Process In Ordered Sequential Update, M. Ebrahi̇m Fouladvand, Farhad Jafarpour

Turkish Journal of Physics

A multi-species generalization of the asymmetric simple exclusion process (ASEP) is studied in ordered sequential and sub-lattice parallel updating schemes. In this model, particles hop with their own specific probabilities to their rightmost empty site and fast particles overtake slow ones with a definite probability. Using Matrix Product Ansatz (MPA), we obtain the relevant algebra, and study the uncorrelated stationary state of the model both for an open system and on a ring. A complete comparison between the physical results in these updates and those of random sequential introduced in [20,21] is made.

A Detour In De Sitter Space While Calculating Vacuum Fluctuatins, M. Hortaçsu

Turkish Journal of Physics

{We study vacuum fluctuations of different gravitational waves by taking a detour in de Sitter space in the intermediate steps. We find finite contributions when the coupling constant is dimensionless, whereas null result persists in the cases with dimensional coupling constants. We also test our method for exactly solvable cases, and show that no spurious perturbative effects are introduced through our method.

Chaos In Closed Isotropic Cosmological Models With Steep Scalar Field Potential, A. V. Toporensky

Turkish Journal of Physics

The dynamics of closed scalar field FRW cosmological models is studied for several types of exponentially and more than exponentially steep potentials. The parameters of scalar field potentials which allow a chaotic behaviour are found from numerical investigations. It is argued that analytical studies of equation of motion at the Euclidean boundary can provide an important information about the properties of chaotic dynamics. Several types of transition from chaotic to regular dynamics are described.

Coherent States For The Hydrogen Atom, Nuri̇ Ünal

Turkish Journal of Physics

We obtained the coherent states for the hydrogen atom by transforming the problem onto the four oscillators in the parametric time at the classical level and quantizing these oscillators. We showed that for the coherent states the mean values of the physical position of the electron satisfy the Keplerian ellipsis and the dispersions of them oscillate in the parametric time.

Skyrmions From Harmonic Maps, Wojtek Zakrzewski

Turkish Journal of Physics

We describe some relations between solitonic solutions of various models in different dimensions. We present some examples and then concentrate on some of our recent work (performed in collaboration with Ioannidou and Piette) \cite{IPZ} \cite{us2} which shows how some harmonic maps from $S^2$ to $CP^{N-1}$ can be used to find nontrivial spherically symmetric static solutions of the $SU(N)$ Skyrme model in 3 dimensions and to generate some of its low energy field configurations.

A Glancing Incidence Exafs Study Of Evaporated Silver Films On Glass, Ahmet Bulut, Bünyami̇n Karabulut, Engi̇n Başaran, James Robinson

Turkish Journal of Physics

A glancing incidence EXAFS experiment has been carried out with evaporated silver films on glass substrates. Prior to EXAFS data collection, a reflectivity curve was performed from which the critical angle for total external reflection of x-rays from surface were determined. The analysed EXAFS data revealed that there is a reduction in the coordination number and an increase in Debye-Waller factor compared to bulk values. These changes were explained in terms of grain size effect and the surface effects of the silver film.

The Effect Of Potassium Doping On Resistive Transitions And Transport Critical Current Of Bulk Ybco High-Tc Superconductors, S. Çelebi̇, A. Öztürk, İ. Karaca, U. Kölemen

Turkish Journal of Physics

We report on observations of the effect of potassium in YBCO (123) high temperature superconductors with nominal composition Y\( _{1-0,2x} \) Ba\( _{2-0.2x} \) K\( _{x} \) Cu\( _{3} \) O\( _{y} \). The electrical resistivity measurements show that the critical temperature T$_{c} \) (R=0) shifted slightly to lower temparature due to the K doping process. This process also decreases the transport critical current density and the activation energy for thermally activated flux flow. The magnetic field dependence of \( j_{c} \) was measured at 77 K after zero field cooling (ZFC) when the applied magnetic field is impressed (ZFCV) …

Internal Photoemission Spectroscopy For A Ptsi/P-Si Schottky Junction, Bülent Aslan, Raşi̇t Turan

Turkish Journal of Physics

Properties of internal photoemission in a PtSi-Si Schottky junction have been studied. The traditional Fowler plot of a detector's photoyield is found to be nonlinear for values close to the barrier height of the junction. It is shown that the model that takes all scattering mechanisms into account provides a successful description for the experimental results. It is also shown that the photoemission spectrum is independent of temperature in agreement with this model. The properties of detector's ambient influence the photoemission spectrum for wavelength of 3 $\mu$m or less. A strong loss in the detector's response is observed at around …

Optical Properties Of Zns Thin Films, M. Y. Nadeem, Waqas Ahmed

Turkish Journal of Physics

Zinc sulfide (ZnS) thin films of different thickness were deposited on Corning 7059 glass substrate at room temperature and high vacuum using resistive heating technique. The film properties investigated include their absorbance / transmittance / reflectance spectra, band gap, refractive index, extinction coefficient, optical conductivity, complex dielectric constant and thickness. The films were found to exhibit high transmittance (60-99\%), low absorbance and low reflectance in the visible / near infrared region up to 1100 nm. However, the absorbance of the films was found to be high in the ultra violet region with peak around 360 nm. The thickness (using quartz …

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 …

Effect Of Calcium, Magnesium, Sodium And Potassium Levels In Seminal Plasma Of Holstein Bulls On Spermatological Characters, Seyfetti̇n Gür, Eşref Demi̇rci̇

Turkish Journal of Veterinary & Animal Sciences

This study was conducted to investigate the levels calcium, magnesium, sodium and potassium in the seminal plasma of bulls, semen volume, sperm motility, sperm concentration and the correlation between these parametres. Five Holstein bulls constituted the material of this study. Twenty ejaculates were collected from each bull and the spermatological characteristics of these ejaculates were determined. Then, seminal plasma was separated from 3ml semen from each ejaculate by centrifugation at 1500g for 20 min at 4 °C. Calcium, magnesium, sodium and potassium concentrations in seminal plasma were determined by atomic absorption spectrophotometry. The average values for calcium, magnesium, sodium and …

Borate Deposits Of Turkey And Argentina; A Summary And Geological Comparison, Cahi̇t Helvaci, Ricardo R. Alonso

Turkish Journal of Earth Sciences

No abstract provided.

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

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

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.

Calcium And Phosphate Excretion In Preeclampsia, Pervi̇n Vural, Cemi̇l Akgül, Mukaddes Canbaz

Turkish Journal of Medical Sciences

In preeclampsia, alterations in renal function, electrolyte and water metabolism are common findings. Recent studies have suggested that preeclampsia is associated with hypocalciuria. A total of 59 women were included in the present study, 15 of whom were nonpregnant (NP) healthy women, 20 normotensive pregnant women (NTP), and 24 pregnant women with severe preeclampsia (PEP). We compared the three groups in terms of calcium and phosphate excretion, and some parameters of renal function such as serum urea, creatinine and creatinine clearance. Urinary calcium and phosphate levels in the PEP group were significantly lower than in the NP group (p< 0.001 and p< 0.01, respectively) and NTP group (p< 0.001 and p< 0.01, respectively). The serum urea levels were higher in the PEP group than in the NP and NTP (p< 0.001) groups. The same pattern of increase in the PEP group was valid for serum creatinine concentrations as compared with the NP (p< 0.01) and NTP (p< 0.001) levels. The glomerular filtration rate measured by creatinine clearance was lower in preeclamptic women than in normotensive pregnant women (p< 0.01). Patients with preeclampsia had significantly lower (p< 0.001) excretion of calcium than the NP and NTP groups (p< 0.001). Likewise, the phosphate levels were lower in women with preeclampsia than in the NP and NTP groups (p< 0.01). There was no correlation between parameters of renal function and calcium or phosphate excretion. Hypocalciuria and hypophosphateuria were found to be important features of severe preeclampsia and probably indirectly are related to the altered renal function seen in toxemia of pregnancy.

Experimentally Developed Secondaryechinococcosis In Pleural And Peritoneal Cavitiesand The Utility Of Serological Tests During Thefollow Up, Kadi̇r Kazez, Mustafa Şahi̇n, Celaletti̇n Vatansev, Yücel Aritaş, Faruk Aksoy, Hüsametti̇n Vatansev

Turkish Journal of Medical Sciences

Secondary echinococcosis is an important complication of hydatid disease and is not rare in the peritoneal cavity. However, the frequency of secondary hydatidosis in the pleural cavity is not very well known. This study was planned to elicit the frequency of secondary cyst development in the pleural cavity, and to compare this with secondary peritoneal hydatidosis. It was also intended to follow up cyst development by serological tests. Twelve white female Island rabbits were used. The mean weight of the rabbits was 2450±420 g. Cystic fluid containing protoscolex, hydatid sand and germinative membrane homogenate was injected via an 18 F …

The Isolation Rate And Antibiotic Resistantpattern Of Helicobacter Pylori In Dyspepticpatients, Esra Ağel, Bengül Durmaz, Mehmet Refi̇k Tevfi̇k, Nergi̇s Aşgin

Turkish Journal of Medical Sciences

In order to determine the isolation rates of Helicobacter pylori in dyspeptic patients, 167 biopsy specimens were examined using different methods, including culturing, microscopy and the rapid urease test. Resistance to commonly used antimicrobials was investigated using the disk diffusion method. Of the 167 specimens, 82(49.1%) were found to be positive for Helicobacter pylori in culture and 72(43 %) were positive in the urease biopsy test. Using Gram staining, Helicobacter pylori were observed in 43 (25.7 %) of the specimens. The resistance rate of the isolates was 53 % for metronidazol, 8% for both clarithromycin and ciprofloxacin, and 4% for …

Comparative Studies On The Production Performances Of Chios And Imroz Breeds Kept Under Semi-Intensive Conditionus Ii. Milk Production, Fleece Yields And Characteristics, Şebnem Gündal Çörekçi̇, Mehmet Evri̇m

Turkish Journal of Veterinary & Animal Sciences

This paper is the second part of a study carried out to reveal the comparative production performances and effect of some environmental factors on the production characteristics of Chios and Imroz ewes kept in a single flock under semi-intensive conditions. In this part of the study milk yields, lactation lengths and fleece weights and characteristics were considered. Mean lactation lengths and milk yield of Chios ewes were 203 days and 73.92 kg respectively; the comparative values for Imroz ewes were 223 days and 102.04 kg respectively. At the first shearing (6 months of age), average fleece weights of Chios and …

A Study Of Preservice Teachers’ Views On The Nature Of Science, Kathlyn K. Yang

Graduate Research Papers

This study was designed for two purposes. The first purpose was to develop a general description of preservice secondary science teachers' views on the nature of science. The second purpose was to compare views held by preservice teachers beginning their first science methods courses to views held by preservice teachers at the end of their second methods course.

The participants of this study consisted of 11 preservice science teachers enrolled in two secondary science methods courses at the University of Northern Iowa. Kimball's Nature of Science Scale (NOSS) (1967-1968) was administered to all participants and selected participants were interviewed.

The …

Family Literacy Project, Laura K. Scully

Graduate Research Papers

The purpose of the family literacy project was to implement a partnership program connecting the Title I reading teacher and the school with parents of children receiving Title I reading services. It involved an effort to promote children's literacy in the home. The partnership emphasized collaboration and encouraged input from parents. The focus of the project was to integrate curricular activities that met the students' current educational needs with literacy activities that already occurred naturally in the home.