Physical Sciences and Mathematics Commons^™

Defect Structure Of Glow Peak 1 In Lif:Mg,Ti (Tld-100), A. Necmeddi̇n Yazici

Turkish Journal of Physics

The possible defect structure of peak 1 of LiF:Mg,Ti (TLD-100) was studied in the present work after different pre-irradiation heat treatments between 80°C and 150°C using the computer glow curve deconvolution (CGCD) method. It was shown that the defect structure of peak 1 is based on colloid centers, Ti^{+4}-3O_{2}^{-}-mixed centers and U_{1}-centers.

Measurement Of Photon-Induced K X-Rays Production Cross Sections For Elements With 62 \Le Z \Le 74, Sabri̇ye Seven

Turkish Journal of Physics

X-ray production cross sections of K\alpha_{1}, K\alpha_{2}, K\beta'_{1} (= K\beta {\ss}_{1} + K\beta_{3} + K\beta_{5}) and K\beta'_{2} (= K\beta_{2} + K\beta_{4} + transitions from higher levels) lines have been measured and theoretically calculated for six elements with 62 \le Z \le 74 at excitation energy of 78.706 keV, the weighted avarage of K conversion x-rays emitted from Bi. The experimental results were compared with theoretically predicted values based on relativistic Hartree-Slater and Hartree-Fock theories, a comparison that was found to be in good agreement to within the experimental uncertainties.

Temperature Dependence Of Galvanomagnetic Properties For Lightly Doped N-Type Si, Aytunç Ateş, Beki̇r Gürbulak, Seydi̇ Doğan, Muhammet Yildirim, Sebahatti̇n Tüzemen

Turkish Journal of Physics

The temperature dependence of Hall and magnetoresistance effects in n-type Si having a resistivity of 1400 {\Omega } cm at room temperature is studied in the temperature range of 210-320 K. The variation of transverse magnetoresistance as a function of temperature is similar to the longitudinal magnetoresistance variation in < 001 > and < 1\bar {1}0 > n-Si the samples. It is observed that, in < 001 > sample, the transverse and longitudinal magnetoresistance variation is greater than that in the < 1\bar {1}0 > sample. In both samples, the temperature dependences of magnetoresistance is in accordance to double space anisotropy parameters. In both samples, the transverse and longitudinal magnetoresistance coefficents increase with increasing …

Micro-Crystallographic, Optical And Transport Studies Of Cd_{0.7} Zn_{0.3} Se : Sb Thin Films, D. S. Sutrave, G. S. Shahane, V. B. Patil, L. P. Deshmukh, B. D. Sarwade

Turkish Journal of Physics

Cd_{1-x}Zn_{x}Se thin film structures doped with various concentrations of trivalent antimony were chemically deposited onto glass-substrates. These structures were then characterised through the XRD, SEM, optical and electrical characterization techniques. The X-ray diffractograms of both as-prepared and Sb-doped samples were obtained and analysed. The analysis revealed that the samples are microcrystalline over the whole range of the doping concentration (0 to 2 mol %). It is striking that the intensities of hexagonal and cubic reflections of CdSe went on increasing with doping concentration upto 0.1 mol % and decreased with further increase in Sb^{3+} content in the film whereas peak …

Effect Of The Zn Concentration On The Characteristic Parameters Of Zn_{X}Cd_{1 - X}S Thin Films Developed By Spraying Pyrolysis Method Under The Nitrogen Atmosphere, Meti̇n Bedi̇r, Refi̇k Kayali, Mustafa Öztaş

Turkish Journal of Physics

The electronic and optical properties of Zn_{x}Cd _{(1- x)}S thin films (0.0 \le x \le 0.7) fabricated using the chemical spray method have been investigated in nitrogen atmosphere. The films are deposited on glass substrates at 420^oC substrate temperature. The related optical data are recorded in the wavelength range 200-700 nm. In addition, the absorption coefficient is determined and correlated with the photon energy in order to estimate the direct transition energy bandgap. The crystallite size and degree of preferential orientation were found to decrease with the increase of x and to improve upon annealing in vacuum at \cong 600^oC. …

Spatial Non-Uniformity Measurements Of Large Area Silicon Photodiodes, Murat Durak, Farhad Samadov, A. Kamuran Türkoğlu

Turkish Journal of Physics

Accurate determination of the responsivity of silicon photodiodes are highly desired in photometry. The change of responsivity over the surface, the so-called spatial non-uniformity, effects power measurements especially in photodiodes with large active areas. To study this effect, first an intensity-stabilized laser source-optics has been established. A purpose-built step-motor controlled two axis micro mechanical stage has been designed to scan the photodiode surface. In this study, the technique and the results of the uniformity mapping of large area research-grade silicon photodiodes which were measured on the purpose-built set-up are presented.

Some Characteristic Properties, Vithal Bhivaba Pujari, V. B. Gaikwad, E. U. Masumdar, P. D. More, L. P. Deshmukh

Turkish Journal of Physics

This paper presents some information regarding (Cd, Hg) Se materials synthesized by a simple chemical growth process and the structural, optical and electrical transport properties. The growth of these films depends on various preparative parameters and deposition conditions such as concentration of the starting materials, pH, temperature, time, speed of mechanical churning, etc., and the reaction kinetics suggests that the films grow into two different phases: one, initialy an almost linear phase; and second, a saturation phase. The deposits were analysed chemically and by an EDS techniques. It has been seen that more than 70% of the materials taken in …

Monitoring The Effect Of Recrystallization And Quenching In Almg_{X} Alloy By Pat, A. Ashour, Nour Zaki El-Said, Emad A. Badawi

Turkish Journal of Physics

Positron annihilation technique (PAT) lifetime measurements have been carried out on AlMg_{x} samples (x = 0.23, 0.85, 1.27 and 1.4 at %) with point defects and dislocations introduced by plastic deformation at room temperature. Clustering of vacancies was observed by quenching using PAT. The samples were annealed at 573 K for 12 hours to homogenize and divided into two sets. The first set of AlMg_{x} (x = 0.23, 0.85 and 1.4 at %) was deformed to 10, 25 and 35% thickness reduction. Isochronal annealing was studied in the range of 300-550 K. In the second set of measurements, AlMg_{x} (x …

Off-Diagonal Matrix Elements And Sum Rules Involving Coulomb And Isotropic Oscillator Functions, Harry A. Mavromatis

Turkish Journal of Physics

Off-diagonal matrix elements and sum rules for the Coulomb and isotropic oscillator systems are obtained from a study of relations between the off-diagonal matrix elements of a general recursion relation.

Revised Stratigraphy And Facies Analysis Of Palaeocene-Eocene Supra-Allochthonous Sediments (Denizli, Sw Turkey) And Their Tectonic Significance, Hasan Sözbi̇li̇r

Turkish Journal of Earth Sciences

A non-metamorphosed sedimentary sequence of Late Palaeocene-Eocene age exposed to the south of Dereköy Village (east of Denizli) was formerly interpreted as the uppermost part of the Menderes Massif. However, detailed field data indicates that the Dereköy succession rests unconformably on the Lycian ophiolitic mélange and thus cannot be accepted as a part of the Menderes sequence. The Dereköy succession consists of shelf to sub-marine sedimentary deposits that begin with a transgressive basal conglomerate, followed by limestone and then grading upward into clastic turbidites. The clastic beds have intra-basinal and extra-basinal fragments derived from carbonate lenses and the Lycian thrust …

Pyrite Deformation Textures In The Deposits Of The Küre Mining District (Kastamonu-Turkey), İlkay Kuşcu, Ayhan Erler

Turkish Journal of Earth Sciences

The Küre volcanogenic massive sulfide deposits lie within the Kastamonu province in the western part of the Pontide tectonic belt of Turkey, and are hosted by ophiolite-related pre-Liassic basaltic sequences. Mineralogical studies of the pyritic massive sulfide deposits of the Küre mining district have shown that the sulfide assemblages, particularly pyrite, have undergone a history of deformation and metamorphism. The Küre volcanogenic massive sulfide deposits show a range of macroscopic and microscopic textures, which are also observed in metamorphosed VMS deposits elsewhere. These textures are cataclastic, annealing and fracture-filling textures which developed in two successive stages; cataclastic texture predominated during …

The Silistar Intrusive, Eastern Srednogorie Zone, Bulgaria: Structural Data And Potential For Porphyry Copper And Epithermal Systems, Radoslav Nakov, Thomas Kerestedjian, Angel Kunov

Turkish Journal of Earth Sciences

The Late Cretaceous Silistar intrusion comprises of gabbros, gabbro-diorites to quartz-diorites and aplites, that were emplaced into a volcano-sedimentary succession of similar age. Structural data suggest that this intrusion is part of a larger, partially exposed body. A dense network of primary and secondary joints, in many places filled with various ore and gangue minerals, is a conspicuous feature of the intrusion. Hydrothermal alteration affecting the intrusion and the wall rocks includes: uralitization (amphibole±epidote), secondary biotitization and propylitization. Propylitic alteration occurred in two stages: high temperature (epidote-actinolite-chlorite) and middle to low temperature (sericite-chlorite-carbonate-epidote and chlorite-sericite-carbonate). Products of later alteration events …

Age And Thickness Of The Lithosphere Within The Western And Eastern Basins Of The Black Sea According To Geophysical Data, Eugeniy Verzhbitsky, Ivan Kuzin, Leopold Lobkovsky

Turkish Journal of Earth Sciences

The ages of the western and eastern basins of the Black Sea have been estimated on the basis of heat-flow data. The obtained ages (70-60 Ma) are in good accord with the time of basins' origin as determined from seismic and magnetic data. During this time, the Black Sea opened as a back-arc basin to the north of the Pontide magmatic arc. The arc prehistory of the Pontides is confirmed by the existence of relict mantle seismicity, which is most active in the eastern Pontides. Nearly synchronous times of origin for the western and eastern basins supports the concept of …

The Use Of A Genetic Algorithm To Evolve Networks For A Natural Language Processing Task, Alexander E. Dimov '02

Honors Projects

In this project a novel approach was taken for performing a natural language task. The task requires a neural network to predict the grammatical category of the next word in a stream of sentences. There are two main reasons why this task is interesting. In natural language processing, it is sometimes very difficult to determine the grammatical category of a word in a sentence when that word could belong to different grammatical categories depending on the context. For example, the word "run" can either be a noun or a verb in a certain sentence. The ability to correctly determine the …

Dimensionality-Reducing Expansion, Boundary Type Quadrature Formulas, And The Boundary Element Method, Tian-Xiao He

Scholarship

This paper discusses the connection between boundary quadrature formulas constructed by using solutions of partial differential equations and boundary element schemes.

Applications Of Bismuth(Iii) Compounds In Organic Synthesis, Ram Mohan, Nicholas Leonard, Laura Wieland

Scholarship

No abstract provided.

Environmental Factors Contributing To The Disaggregation Of A Colonial Cyanoprokaryote And Its Influence On Picoplankton Abundance Within Lake Joyce, Virginia, Lewis F. Affronti Jr., B. Thomas Duquette

Virginia Journal of Science

A colonial cyanoprokaryote, Aphanocapsa holsatica and autotrophic picoplankton abundance were monitored weekly over a two year period in Lake Joyce, Virginia. Significant differences were observed in both the cyanoprokaryote and picoplankton abundance over the study period and an inverse relationship was observed between these two plankton groups. Disaggregation of colonies was shown to contribute to picoplankton populations where water temperature and precipitation input apparently trigger colony dispersion. This relationship is suggested to occur in other aquatic habitats. Results of this work and its implications for ecosystem dynamics are discussed.

Bibbies, Salinity And A Question Of Balance, Gael Bell, Bruce Radys, John Goodlad, Joy Kilian

Books & book chapters

This book is designed to be used in conjunction with the manual 'Salinity in the classroom'.

Published with the assistance of Greening Australia Western Australia, Department of Conservation and Land Management, Department of Education Western Australia.

Crustal Fissuring On The Crest Of The Southern East Pacific Rise At 17˚15'-40'S, Dawn J. Wright, Rachel M. Haymon, Scott M. White, Ken C. Macdonald

Faculty Publications

Fissure densities and widths have been mapped along the axial zone of the superfast spreading southern East Pacific Rise (EPR) at 17_150–400S with the near-bottom DSL-120 and Argo II imaging systems. We observe that the youngest lava flows (on a relative age scale) are sparsely fissured and that there is a cumulative increase in fissure abundance with time that produces a strong positive correlation between fissure density and relative age of lava flows. Average fissure widths were used to estimate fissure depths. In the 17_150–400S area, calculated fissure depths are estimated to extend below the seismic layer 2A/2B boundary, and …

Collisional And Radiative Processes In High-Pressure Discharge Plasmas, Kurt H. Becker, Peter F. Kurunczi, Karl H. Schoenbach

Bioelectrics Publications

Discharge plasmas at high pressures (up to and exceeding atmospheric pressure), where single collision conditions no longer prevail, provide a fertile environment for the experimental study of collisions and radiative processes dominated by (i) step-wise processes, i.e., the excitation of an already excited atomic/molecular state and by (ii) three-body collisions leading, for instance, to the formation of excimers. The dominance of collisional and radiative processes beyond binary collisions involving ground-state atoms and molecules in such environments allows for many interesting applications of high-pressure plasmas such as high power lasers, opening switches, novel plasma processing applications and sputtering, absorbers and reflectors …

Electrical Network-Based Time-Dependent Model Of Electrical Breakdown In Water, R. P. Joshi, J. Qian, K. H. Schoenbach

Bioelectrics Publications

A time-dependent, two-dimensional, percolative approach to model dielectric breakdown based on a network of parallel resistor–capacitor elements having random values, has been developed. The breakdown criteria rely on a threshold electric field and on energy dissipation exceeding the heat of vaporization. By carrying out this time-dependent analysis, the development and propagation of streamers and prebreakdown dynamical evolution have been obtained directly. These model simulations also provide the streamer shape, characteristics such as streamer velocity, the prebreakdown delay time, time-dependent current, and relationship between breakdown times, and applied electric fields for a given geometry. The results agree well with experimental data …

Mid-Ordovician (Late Darriwilian) Conodonts From The Southern-Central Taurides, Turkey: Geological Implications, Hüseyi̇n Kozlu, M. Cemal Göncüoğlu, Graciela N. Sarmiento, M. Ali̇ Gül

Turkish Journal of Earth Sciences

The Tekmen Member of the Seydişehir Formation of the Silifke-Aydıncık Nappe is exposed between the towns Silifke and Aydıncık, in the central Taurides, southern Turkey. The member is composed of sandy limestones with interbeds of reddish shales. Distinctive depositional features of the carbonates and associated siliciclastics are suggestive of a mixed carbonate-siliciclastic tempestite-type deposition in a shelf environment. The conodont fauna from the Tekmen Member includes taxa that are known from the Baltoscandian region and are referred to the Darriwilian, being the first Middle-Ordovician finding from Turkey. A late Darriwilian (late Lasnamägian to Uhakun) age migth be attributed to the …

Implementation Of An Integrated Quality Assurance Program For Ct-Tps Process, Junqing Wu

LSU Master's Theses

Systematic constancy and accuracy of a treatment planning system (TPS) are crucial for the entire radiation treatment planning process (TPP). The Quality Assurance (QA) of individual components does not necessarily lead to satisfying performance of the whole process due to the possible errors introduced by the data transfer process between components and other fluctuations. However, most of current QA for TPS is confined to the treatment planning computers. In this study, a time efficient and integrated CT-TPS QA procedure is presented, which starts at the beginning of the TPS input --- Computer Tomograhpy (CT). The whole QA procedure is based …

Studying The Functional Genomics Of Stress Responses In Loblolly Pine With The Expresso Microarray Experiment Management System, Lenwood S. Heath, Naren Ramakrishnan, Ronald R. Sederoff, Ross W. Whetten, Boris I. Chevone, Craig Struble, Vincent Y. Jouenne, Dawei Chen, Leonel Van Zyl, Ruth Grene

Mathematics, Statistics and Computer Science Faculty Research and Publications

Conception, design, and implementation of cDNA microarray experiments present a variety of bioinformatics challenges for biologists and computational scientists. The multiple stages of data acquisition and analysis have motivated the design of Expresso, a system for microarray experiment management. Salient aspects of Expresso include support for clone replication and randomized placement; automatic gridding, extraction of expression data from each spot, and quality monitoring; flexible methods of combining data from individual spots into information about clones and functional categories; and the use of inductive logic programming for higher-level data analysis and mining. The development of Expresso is occurring in parallel with …

On Unit Sum Numbers Of Rational Groups, Brendan Goldsmith, Christopher Meehan, S. Wallutis

Articles

The unit sum numbers of rational groups are investigated: the importance of the prime 2 being an automorphism of the rational group is discussed and other results are achieved by considering the number and distribution of rational primes which are, or are not, automorphisms of the group. Proof is given of the existence of rational groups with unit sum numbers greater than 2 but of finite value .

K(Π, 1) For Artin Groups Of Finite Type, Colum Watt, Thomas Brady

Articles

This paper is a continuation of a programme to construct new K(π, 1)’s for Artin groups of finite type which began in [4] with Artin groups on 2 and 3 generators and was extended to braid groups in [3]. These K(π, 1)’s differ from those in [6] in that their universal covers are simplicial complexes. In [4] a complex is constructed whose top-dimensional cells correspond to minimal factorizations of a Coxeter element as a product of reflections in a finite Coxeter group. Asphericity is established in low dimensions using a metric of non-positive curvature. Since the nonpositive curvature condition is …

Epr Of Co(Ii) As A Structural And Mechanistic Probe Of Metalloprotein Active Sites: A Review Of Studies On Aminopeptidase, Brian Bennett

Physics Faculty Research and Publications

Co(II) can often be substituted for Zn(II) in zinc-dependent metalloenzymes to provide spectroscopically accessible forms of the enzymes. Co(II) is an excellent spectroscopic probe as it is both optically active and EPR active. Further, its fast relaxation properties make it a useful paramagnetic shift reagent in NMR. In EPR, the dependence of the spectra of high-spin Co(II) on E/D and the sensitivity of the resolvability of the ⁵⁹Co hyperfine structure to strain terms allow structural information to be inferred from the EPR spectra. In addition to its useful spectroscopic properties, Co(II) is often an extremely good functional mimic of …

[Introduction To] Data Structures With Java: A Laboratory Approach, Joe Kent, Lewis Barnett Iii

Bookshelf

This book is designed to present the key topics in the second course for computer science students using the Java programming language. For convenience, we cover exceptions and file operations in Java, although this may have been covered in the first course. We also cover material on the binary representation of data and Java's bitwise operations, with applications.These are topics needed for computer organization an operating systems courses.

[Introduction To] Generalized Analytic Continuation, William T. Ross, Harold S. Shapiro

Bookshelf

The theory of generalized analytic continuation studies continuations of meromorphic functions in situations where traditional theory says there is a natural boundary. This broader theory touches on a remarkable array of topics in classical analysis, as described in the book. This book addresses the following questions: (1) When can we say, in some reasonable way, that component functions of a meromorphic function on a disconnected domain, are "continuations" of each other? (2) What role do such "continuations" play in certain aspects of approximation theory and operator theory? The authors use the strong analogy with the summability of divergent series …

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Year 3, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.