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A Correlation Of Thin Lens Approximation To Thick Lens Design By Using Coddington Factors In Lens Design And Manufacturing, Ömer Faruk Farsakoğlu, D. Mehmet Zengi̇n, Hi̇kmet Kocabaş

Turkish Journal of Physics

The effect of Coddington factors on aberration functions has been analysed using thin lens approximation. Minimizing spherical aberrations of singlet lenses using Coddington factors in lens design depending on lens manufacturing is discussed. Notation of lens test plate pairs used in lens manufacturing is also presented in terms of Coddington shape factors.

Cover And Contents

Turkish Journal of Physics

No abstract provided.

Some String Cosmological Models In Cylindrically Symmetric Inhomogeneous Universe, Hüsnü Baysal, İlhami̇ Yavuz, İsmai̇l Tarhan, Uğur Camci, İshan Yilmaz

Turkish Journal of Physics

The aim of this paper is to investigate the behavior of a string in the cylindrically symmetric inhomogeneous cosmological model. It has been assumed that expansion \theta in the model is proportional to \sigma^1_1 of the eigenvalue of the shear tensor \sigma^{\mu}_{\nu}. Also, various physical and geometrical properties of the model have been discussed.

Lattice Dynamical Calculations For The Co-Fe Alloys, Kemal Çolakoğlu, Yasemi̇n Özteki̇n Çi̇ftçi̇

Turkish Journal of Physics

Lattice dynamical calculations are performed on Co_{0.92}-Fe_{0.08} alloy with fcc structure. The de Launay Angular force (DAF) model is used to represent the ion-ion intreactions, and the long-range ion-electron interactions are accounted for along the lines of the Sharma-Joshi scheme. The frequency distribution and the lattice specific heat are also computed for the studied alloys. The present theoretical results are in reasonable agreement with the available experimental data.

The Investigation Of The Thermoluminescence Emission Bands Of Lif:Mg,Ti (Tld-100) By A Simple Developed Model, A. Necmeddi̇n Yazici, Z. Öztürk, M. Bedi̇r

Turkish Journal of Physics

In this study, a new simple model based on the classical treatment of lattice vibrations and the Franck-Condon principle is developed to describe the shape of thermoluminescence (TL) emission bands of crystalline solids. According to developed model, shape of the emission band has a Gaussian form and depends on just two physical parameters: peak energy E_{0} and broadening of emission spectra U. In order to demonstrate the success of the developed model, the emission spectra of dosimetric material LiF:Mg,Ti (TLD-100) was also measured. Then, a computerised best-fit program including the developed model was used to analyse the emission spectra. The …

Second Order Elastic Constants And Some Thermoelastic Properties Of Alkali Halides Using Woodcock Potential, Harun Reşi̇t Yazar, Sedat Ağan, Kemal Çolakoğlu

Turkish Journal of Physics

Second Order Elastic Constants (S.O.E.C) of NaCl-type crystals have been calculated using the Woodcock potential. Short-range repulsive interactions have been included up to second-nearest neighbors. This potential form represents the composite form of the inverse power dependence and exponential dependence of the repulsive energy on interionic distance. Some thermoelastic and thermodynamic properties such as Anderson-Grüneisen parameters \delta _{T}, and \delta _{S}, Volume thermal expansion coefficient \beta and Grüneisen gama \gamma _{G} have been calculated in terms of calculated values of S.O.E.C and Third Order Elastic Constant ( T.O.E.C).

Built-In Potential Measurements In A-Si:H P-I-N Solar Cells, Ruhi̇ Kaplan, Bengü Kaplan

Turkish Journal of Physics

We have measured the open-circuit voltage V_{oc} and the short-circuit current density J_{sc} of amorphous silicon (a-Si:H) p-i-n solar cells deposited by radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) at different monochromatic illuminations, and temperatures. From the measurements, the built-in potential V_{bi} was determined by using two different methods: activation energy and differential temperature. The results from both methods were analyzed and compared as a function of excitation wavelength. It was observed that there is good agreement between the two methods. We found that V_{bi} increases until about 650 nm, and then decreases with increasing wavelength. This behaviour is explained and …

Space Charge Limited Current At High Fields In Al-Ge-Al Surface Barrier Devices, A. I. Mukolu

Turkish Journal of Physics

The current-voltage (I-V) characteristics of Aluminium-Germanium-Aluminium (Al-Ge-Al) surface barrier devices at different fields (

On The Evaluation Of Determinantal Wave Functions In Open-Shell Hartree-Fock Theory, I. I. Guseinov, Ramazan Demi̇r

Turkish Journal of Physics

Slater method is modified for the evaluation of determinantal wave functions appearing in open-shell Hartree-Fock (HF) theory [1]. Using modified Slater method we have calculated, as an example, the orbital energies and the wave functions of terms obtained from the electronic configuration of a ground state of an N-atom system in the Hartree-Fock-Roothaan (HFR) approximation. The modified determinantal method introduced in this paper can be of considerable help and importance in the simplification and calculation of atomic and molecular electronic structure.

Lattice Changes In Shape Memory Cuznal Alloys On Aging At Room Temperature, Seyfetti̇n Çakmak, Ekrem Artunç, Nejdet Kayali, Osman Adigüzel

Turkish Journal of Physics

The aging behavior of CuZnAl martensites (Cu-21.62 wt.% Zn-5.68 wt.% Al and Cu-24.98 wt.% Zn-4.43 wt.% Al) at about 297 K was studied by analyzing diffraction line profiles obtained by X-ray diffractometry. For the alloys, the change of the lattice parameters and the tetragonality associated with the aging time at room temperature were investigated. The habit planes versus the aging time at room temperature were calculated using the De Vos-Aernoundt-Delaey model, based on the crystallographic theory of Wechsler-Lieberman-Read(WLR), and from the DO_{3}\rightarrow 18R martensite transformation theory.

Physical Properties Of Melt-Cast Annealed Bi_{1.6}Pb_{0.4}Sr_{2}Ca_{3}Cu_{4} O_{12} Compound, Ati̇lla Coşkun, Beki̇r Özçeli̇k, Keri̇m Kiymaç

Turkish Journal of Physics

A Bi_{1.6}Pb_{0.4}Sr_{2}Ca_{3}Cu_{4}O_{12} compound was produced by melt-casting method. The microstructure of the sample was studied by Scanning Electron Microscopy. Phase analysis was carried out by X-ray diffraction patterns and EDAX. The electrical resistance exhibites the existance of a superconducting phase with an onset temperature T_{c} at 110 K along with a minor phase with an onset T_{c} at 80 K. It has been found that the superconducting phase temperature T_{c} increases with increasing sintering temperature.

Effect Of Nitriding On Phase Transformations In The Fe-Mn Alloys, K. G. Binnatov, I. I. Ali-Zade, A. O. Mekhrabov

Turkish Journal of Physics

We present results concerning the nitriding effects on phase transformations in Fe -- 40 at. % Mn and Fe -- 50 at. % Mn alloys. These alloys were studied by means of X-ray diffraction and Mössbauer-effect spectroscopy methods at room temperature. Results indicate that, after nitriding, in the absorption spectra of these alloys appears lines with hyperfine field H\sim 330 kOe which corresponds to the field on the ^{57} Fe nuclei in the \alpha -Fe. Annealing of the alloys at 650 ^oC temperature (nitriding temperature) in argon atmosphere do not change the form of the M\\"{o}ssbauer absorption spectra. It appears …

The Effect Of Phonon Drag Of Charge Carriers In In_{1 - X} Ga_{X} Sb, Sadiyar Ahmedoglu Zeynalov

Turkish Journal of Physics

The temperature dependencies of the thermal power a_{0} and thermal conductivity \kappa in two samples of In_{1 - x} Ga_{x}Sb (x=0.65 and 0.45) doped by {Te\sim } 0.001 at\%, with electron concentration n = 5.9 \cdot 10^{16} and 1.3 \cdot 10^{17} cm^{ - 3} (at 100K), have been investigated. It is shown that in In_{0.35}Ga_{0.65}Sb a_{0} increases with decreasing T below 50K. At 14K a_{0} passes through maximum and it falls sharply with decreasing T. It is shown that the maximum value of a_{0} is in agreement with the maximum value of \kappa . In In_{0.55}Ga_{0.45}Sb, starting from T = …

Characteristics Of The Weathering Zones Developed Within The Tuffs Of The Midas Monument, Tamer Topal, Burak Sözmen

Turkish Journal of Earth Sciences

The Midas monument, an impressive cult facade located in the southern part of the Eskişehir province in central Anatolia, Turkey, was made within tuffs (white and pink), which now have deterioration problems. In this study, the depth and characteristics of the weathering zones that have developed in the white and pink tuffs have been investigated through thin-section studies, X-ray powder diffractometry, methylene blue adsorption tests, major-element analyses, and some index parameters. It has been determined that the feldspar minerals are mechanically fractured due to weathering. The tuffs contain small amounts of clay minerals. An approximately 1-cm-thick silica-rich zone has developed …

Development Of A Basic Gis Database For The Yeşilırmak Watershed Provinces Using Satellite Images And Other Data, Hülya Yildirim, Erhan Alparslan, Mehmet Emi̇n Özel, Ci̇hangi̇r Aydöner, Samuray Eli̇taş, Nalan Jale Di̇van, Mehmet Dağci, Asli Süha Dönertaş

Turkish Journal of Earth Sciences

Remote-sensing and geographic-information-systems (GIS) techniques were jointly used in this study to establish a GIS database system for the Yeşilırmak watershed provinces, which include Amasya, Tokat, Çorum, Yozgat and Samsun. Composite multicolour images (down to 6 m resolution) from the LANDSAT TM and Indian IRS C/D satellites, land-use/land-cover maps derived from these images, road networks, soil information, digital terrain model, slope and aspect information derived from digital elevation data and meteorological data at province level are the major constituents of this database. A 'project office' has been established with trained personnel at each province centre to effectively use the resultant …

Whales, Meg Gammon Schroeder

Graduate Research Papers

Children develop thinking-language abilities through involvement in the language processes. A print-rich environment representing the many genres of literature extended across the curriculum offers meaningful experiences with the language functions. Such literature experiences and related expressive activities can provide in-depth study in the content areas, expanding the understanding of units' concepts and related vocabulary.

A science unit on whales for kindergarten was enriched through literature experiences. The activities were presented through teacher-directed sessions and student-initiated activities available in the learning centers. The result of this extensive print-rich environment was in-depth study and enthusiastic responses on the part of the students.

Alternate Curriculum In Reading For Grade Four, Julie A. Schmit

Graduate Research Papers

Julie A. Schmit, a fourth grade teacher, specifically designed the two reading alternate units. These units were designed to provide challenging reading and learning experiences for talented and gifted students in grade four. These units provide challenging, above grade level materials and activities for the students whose reading, vocabulary, and language skills are advanced to such a degree that they would derive greater educational benefit from working with alternate materials.

An Instructional Project Using Physical Knowledge Activities As A Catalyst To Develop Children's Literacy Skills In A Constructivist Preschool Classroom, Patricia A. Wehr

Graduate Research Papers

This instructional project planned and integrated literacy within physical knowledge activities for young children based on International Reading Association, National Research Council and National Association for the Education of Young Children guidelines. The project presented children with a variety of ramps and other physical knowledge activities. Children's engagement was preserved through digital pictures. The children utilized these pictures to individually construct stories orally and in script. Instruction for three dimensions of emergent literacy was provided: concepts about print, phonemic awareness, and reproduction of the child's correctly printed signature. As the project progressed, the activities and the stories grew in complexity. …

Sail Online, Beverly J. Ewert Anderson

Graduate Research Papers

The purpose of this project was to create an online course for a selected group of fourth and fifth grade talented and gifted students. The study, limited to three elementary buildings in the Bettendorf Community School District, Bettendorf, Iowa, was conducted in the Spring of 2001. Twenty-two students from the Talented and Gifted program, SAIL, (Services for Academically Inquisitive Learners) were selected to participate. SAIL Online was an interactive closed web site that provided tools for instruction, research, teacher/student communication, and peer interaction. The project was used to discover if an affective learning community would develop through online communication. The …

A Plan For Implementing Cooperation Between Home School Educators And Public Schools In Buena Vista County, Iowa, Mary Kohnen

Graduate Research Papers

Home school education is a choice that more parents are selecting for their children in today's world. Parents may decide to home school their children for a variety of reasons. Public schools can begin to cooperate with home school parents and assist in the education of home school students by offering the use of school resources. The purpose of this project was to develop a core collection of resources, provide a listing of services in the school library for home school families in Buena Vista County, Iowa schools. It was also intended to develop an informational brochure for home school …

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Turkish Journal of Biology

No abstract provided.

Cover And Contents

Turkish Journal of Biology

No abstract provided.

Cover And Contents

Turkish Journal of Biology

No abstract provided.

Cover And Contents

Turkish Journal of Biology

No abstract provided.

The Problem Of A Viscoelastic Cylinder Rolling On A Rigid Half-Space, John Murrough Golden, G.A.C. Graham

Articles

The problem of a viscoelastic cylinder rolling on a rigid base, propelled by a line force acting at its centre, is solved in the noninertial approximation. The method used is based on a decomposition of hereditary integrals developed by the authors in previous work, and on the viscoelastic Kolosov-Muskhelishvili equations which are used to generate a Hilbert problem. In this formulation, the problem reduces to a nonsingular integral equation in space and time, which simplifies under steady-state conditions and for exponential decay materials, to algebraic form. There are also two subsidiary conditions.

In the case of a standard linear model, …

Chronostratigraphy Of The Crp-3 Drillhole, Victoria Land Basin, Antarctica, M. J. Hannah, F. Florindo, David M. Harwood, Christopher R. Fielding, Cape Roberts Science Team

Department of Earth and Atmospheric Sciences: Faculty Publications

An 823 m thick glaciomarine Cenozoic section sitting unconformably on the Lower Devonian Beacon Supergroup was recovered in CRP –3. This paper reviews the chronostratigraphical constraints for the Cenozoic section. Between 3 and 480.27 mbsf 23 unconformity bounded cycles of sediment were recorded. Each unconformity is thought to represent a hiatus of uncertain duration. Four magnetozones have been recognised from the Cenozoic section. The record is complex with several “tiny wiggles” recorded throughout. Biostratigraphical or Sr ages, which could be used to link these magnetozones to the magnetic polarity time scale are restricted to the upper 190 m of sediment. …

Differential Diagnosis Or Distortion?, Gary Sloboda

University of San Francisco Law Review

No abstract provided.

Insights- March 2001, University Relations Staff

Insights

No abstract provided.

Insights- Jun/Jul. 2001, University Relations Staff

Insights

No abstract provided.

Insights- August 2001, University Relations Staff

Insights

No abstract provided.