Physical Sciences and Mathematics Commons^™

The Eect Of Exposure Time To Clean Room Air On Characteristic Parameters Of Au /Epilayer N-Si Schottky Diodes, M. Sağlam, Ç. Nuhoğlu, E. Ayyildiz, A. Türüt, H.A. Çeti̇nkara

Turkish Journal of Physics

A study has been made on determination and comparison of current-voltage (I-V) and capacitance-voltage (C-V) characteristics parameters of $Au/n-Si$ Schottky barrier diodes (SBDs) with and without thin native oxide layer fabricated on $n$-type $Si$ grown by LPE (Liquid-phase Epitaxy) technique. The native oxide layer with different thicknesses on chemically cleaned on $Si$ surface were obtained by exposing the surfaces to clean room air before evaporating metal. The native oxide thicknesses of samples D2, D3, D4 and D5 are in the form $D2 < D3 < D4 \leq D5$, depending on the exposing time. It has been seen that the values of barrier height $\Phi_b$ of samples D2(0.64 eV), D3(0.66 eV), D4(0.69 eV) and D5(0.69 eV) with the interfacial layer increased with increasing the exposure time and tended to that of the initial sample D1 (nonoxidezed sample, 0.74 eV), and thus also their I-V and C-V curves. The reverse current of sample D1 showed slight nonsaturating behavior. This ''soft'' behavior has been ascribed to the spatial inhomogeneity in the barrier heights at the MS interface. In particular, reverse bias curves of samples D2, D3, D4 and D5 have shown excellent saturation which may be attributed to the passivation of the semiconductor surface states by the native oxide layer which reduces the penetration of the wave functions of electron in the metal into the semiconductor. Especially, the I-V characteristics and experimental parameters of our devices are in agreement with recently reported results revealed by the pulsed surface photovoltage technique for the electronic properties of the HF-treated Si surface during initial oxidation in air.

Nanosecond Duration Broadband Luminescence Of Quartz Glasses, Maruf A. Kasymdzhanov, Pulat K. Khabibullaev, Saidislam S. Kurbanov

Turkish Journal of Physics

The results of investigations of luminescence, excited by radiations of $N_2$- and $Nd^{3+}$: YAG-lasers ($\lambda = 337 nm, \lambda = 532 nm$) in high purity quartz glasses are reported. The luminescence has broad spectrum (350-850 nm) and very short duration (1-20 ns).

Magnetic Domain Structures In As-Quenched And Annealed Fe_{78}B_{13}Si_9 Metallic Glass Ribbons, Yücel Bi̇rol

Turkish Journal of Physics

Among various soft magnetic materials, ferromagnetic glasses are superior to their crystalline counterparts as they possess no magnetocrystalline anisotropy owing to a non-crystalline structure. However, ferromagnetic glasses carry residual stresses and thus anisotropies of magnetostrictive origin in the as-quenched state. These stresses have an adverse effect on the magnetic softness and should be relieved in order to improve magnetic performance, particularly in magnetostrictive alloys. In the present work, the domain structures of Fe$_{78}$B$_{13}$Si$_9$ metallic glass, a highly magnetostrictive alloy, are characterized in the as-quenched and annealed states. The annealing treatments were carried out over a wide temperature range extending from …

Economic Analysis And Comparison Of Two Solar Energy Systems With Domestic Water Heating Systems, R. Kayali

Turkish Journal of Physics

In this work, an economic analysis of different types of thermosiphons and geysers and flat plate collectors and solar ponds employeed in conventional solar energy systems used in houses is analized and the results obtained for these systems are compared with each other. These comparisons show that when the inflation rate is 50\% or less solar energy systems are more economical than the other conventional systems, except for conventional systems in which solid fuels are used. If the calculations are done assuming that the consumer credit interest rate varies between 55-70\%, it is seen that solar energy systems will only …

Domain Structures Of Epitaxial Perovskite Ferroelectric Films: Part I. Theory, S. Pamir Alpay, Alexander L. Roytburd

Turkish Journal of Physics

Possible equilibrium domain structures due to elastic interactions between the film and the substrate as a result of a cubic-tetragonal transformation observed in epitaxial perovskite ferroelectric films are analyzed. Domain structures are compared in terms of their elastic energies. The formation of both two- and three-domain states is taken into account. Maps which shows domain stability regions are developed in coordinates of misfit strain and tetragonality of the lattice of the ferroelectric phase.

Observation Of Events At Very High Q^2 In E^+P Collisions At Hera, A. Wagner

Turkish Journal of Physics

Data collected at the $e^+p$ collider HERA at DESY by the experiments H1 and ZEUS have allowed to probe a previously inaccessible domain of very large $Q^2$ in deep-inelastic $ep$ scattering. For $Q^2 > 15000 GeV^2$ both experiments see more events than expected assuming the Standard Model of deep-inelastic scattering. In this report the observed events, the theoretical expectations and their comparison are discussed.

A Review Of E^+E^- Linear Colliders, D. Trines

Turkish Journal of Physics

No abstract provided.

Testing Deca-Tev Unified Compositeness At The 4 Tev \Mu_+\Mu_-Colliders, Vasily V. Kabachenko, Yury F. Pirogov

Turkish Journal of Physics

In the framework of the unified compositeness of leptons, quarks and Higgs bosons, the hidden local symmetry $\hat H_{loc}=SU(2)_L\times U(1)_Y$ with the heavy composite vector bosons, in addition to the SM gauge bosons, is briefly described. Supplementary hypothesis of the vector boson dominance (VBD) of the SM gauge interactions is considered. It is argued that this should produce the universal dominant residual interactions of the SM composite particles, i.e., all of the fermions and Higgs bosons. Restrictions on the universal residual fermion-fermion, fermion-boson and boson-boson interactions due to the VBD are investigated. Manifestations of the residual interactions at the 4~TeV …

A Proposal For A Measurement Of The Nucleon Form Factors At An Asymmetric E^+E^- Linac-Ring Collider, R. Baldini, C. Bini, P. Patteri

Turkish Journal of Physics

The neutron electromagnetic form factors have been measured for the first time in the time-like region in the $Q^2$ range between 3.6 and 6 $GeV^2$ by the FENICE experiment. The results show some unexpected features. First the neutron magnetic form factor turns out to be larger than the proton one, the neutron electric form factor being negligible. Then there are indications of a narrow structure very near the $N\overline{N}$ threshold, in the e^+e^- multihadronic annihilation. A new, high statistics experiment is needed to clarify the indications. An asymmetric, unconventional, linac-storage ring collider is proposed, using one of the existing high …

Main Parameters Of Linac-Ring Type E-Nucleus And \Gamma-Nucleus Colliders, Ş. Turköz

Turkish Journal of Physics

The main parameters of linac-ring type e-nucleus and $\gamma $-nucleus colliders are considered. It is shown that the reasonable luminosities at the multi-TeV energies can be achieved.

Production Of Susy Particles In Polarized \Gammap Collisions, A. Kandemi̇r

Turkish Journal of Physics

We discuss the production of several SUSY particles in the high energy collisions of the real photons off the protons within the MSSM. The polarizations of the colliding beams are also considered. The discovery mass limits for the squark and gluinos are presented and we conclude that the capacity of the future TeV scale $\gamma p$ colliders is quite promising in the search for SUSY particles.

Resummation Of Ir Renormalons In A Single Meson Photoproduction, Shahin S. Agaev

Turkish Journal of Physics

Single pseudoscalar and vector mesons hard semi-inclusive photoproduction $\gamma h\rightarrow MX $ via higher twist mechanism is calculated using the QCD running coupling constant method. It is proved that in the context of this method a higher twist contribution to the photoproduction cross section cannot be normalized in terms of the meson electromagnetic form factor. The structure of infrared renormalon singularities of the higher twist subprocess cross section and the resummed expression (the Borel sum) for it are found. Comparisons are made with earlier results, as well as with leading twist cross section. Phenomenological effects of studied contributions for $\pi, …

Photoconductivity Studies Of Crystalline Si:H P-I-N, Ruhi Kaplan, Bengü Kaplan

Turkish Journal of Physics

Optically modulated photoconductivity (PC) properties of hydrogenated crystalline silicon (c-Si:H) with p-i-n junctions were investigated by frequency-resolved spectroscopy in the temperature range 20-290 K. The PC lifetime measurements of c-Si:H p-i-n show a second lifetime distribution which only dominates at low temperature under low illumination levels of excitation. Unlike the room temperature single lifetime distribution seen in c-Si:H p-i-n, the maximum of this second lifetime distribution shifts to longer times when the excitation intensity decreases, which reconciles with non-geminate pair recombination and thus the distant-pair model. In addition to lifetime measurements, the direct current-voltage (I-V) characteristics, the excitation light intensity- …

Multiple Scales Method For A Matrix Kdv Equation, Mehmet Naci Özer

Turkish Journal of Physics

In this paper the method of multiple scales is used to derive an integrable matrix non-linear Schrödinger equation (MNLS) as an amplitude equation from the Matrix Korteweg-de Vries equation (MKdV) associated with symmetric spaces. Then the integrability of the MNLS equation is deduced by the derivation of the spectral problem for the MNLS equation from the spectral problem for the MKdV equation.

Quantum Integrable Systems Of The Group Su(1, 1), Mehmet Sezgi̇n, Yılmaz Asad Verdi̇yev

Turkish Journal of Physics

Quantum integrable systems related with SU(1, 1) group manifold or hyperboloid [x, x] = x^2_1 + x^2_2 - x^2_3 - x^2_4 = 1 in spherical, hyperbolic and parabolic coordinates systems are considered. The explicit expressions for waves functions, spectra and S-matrices are given.

Preparation For Sci-Tech Librarianship: Results Of A Survey, John Sandy, Mary Frances Lembo, James Manasco

Sci-Tech News

No abstract provided.

Java Grande Forum Report: Making Java Work For High-End Computing, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

This document describes the Java Grande Forum and includes its initial deliverables.Theseare reports that convey a succinct set of recommendations from this forum to SunMicrosystems and other purveyors of Java™ technology that will enable GrandeApplications to be developed with the Java programming language.

The Use Of Red Mud/Gypsum To Reduce Water Pollution From Sandy Soils Used For Vegetable Production, Ian Mcpharlin, W. J. Robertson, R. C. Jeffery

Research Reports

An important domestic and export vegetable industry is located on the sands of the Swan Coastal Plain (SCP) in Western Australia. The total value of the vegetable industry on the SCP was estimated at $90M in 1996/7 or about 50% of the total value of the industry. This vegetable production has been located on good quality sands such as the Spearwood and yellow Karrakatta sands, close to the coast, since the 1950s. However in recent years competition for this land for urban and industrial use has forced vegetable production onto soils with poorer water and phosphorus retention capacity such as …

Planning To Grow Vegetables Commercially, John Burt, Peter Gartrell

Bulletins 4000 -

This Bulletin was developed by Department of Agriculture in recognition of the increasing complexity and competitiveness in establishing a commercial vegetable enterprise. The information in this Bulletin will provide you with a useful guide to assess your likelihood of succeeding in vegetable production.

Vegetable production is not an easy lifestyle. It is a highly competitive environment with the industry consisting of growers with big investments and years of experience and knowledge. Horticultural farms require a large amount of capital and time and are increasingly expanding and becoming more specialised.

If you are serious about growing vegetables, work through this Bulletin …

1997 Inventory For Spiranthes Diluvialis Sheviak In Western Nebraska: A Final Report, Volume I, Terri Hildebrand

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This study resulted from an agreement between Nebraska Game and Parks Commission (NGPC) and the United States Fish and Wildlife Service (USFW). After the 1996 discovery of Spiranthes diluvialis, in western Nebraska, NGPC was seeking to determine the extent of the Nebraska population. Information on the wet meadow community of orchid occurrence in Nebraska and eastern Wyoming was needed. This report includes descriptions of communities inventoried, Spiranthes diluvialis populations, and additional species monitored by Nebraska and Wyoming Natural Heritage programs.

The 1996 discovery of Spiranthes diluvialis in Nebraska by Hazlett merited the need for further inventory for the species …

1997 Inventory For Spiranthes Diluvialis Sheviak In Western Nebraska: A Final Report, Volume Ii, Terri Hildebrand

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This study resulted from an agreement between Nebraska Game and Parks Commission (NGPC) and the United States Fish and Wildlife Service (USFW). After the 1996 discovery of Spiranthes diluvialis, in western Nebraska, NGPC was seeking to determine the extent of the Nebraska population. Information on the wet meadow community of orchid occurrence in Nebraska and eastern Wyoming was needed. This report includes descriptions of communities inventoried, Spiranthes diluvialis populations, and additional species monitored by Nebraska and Wyoming Natural Heritage programs.

Between May and September 1997, potential Spiranthes diluvialis habitat was inventoried for occurrences of the orchid. For all sites …

Composition And Environmental Assessment Of Soils From United Arab Emirates, Torfa Alsheba Khames Alsheriani

Theses

The study focuses on the mineral and chemical composition, the textural characters and environmental assessment of some soils from the UAE. About forty soil samples were collected from AI Ain District and the Eastern Mountain District. Soils in AI Ain and its suburb are strongly influenced by the aeolian sedimentation, while those of the Eastern Mountain are formed in narrow valleys strikingly close to ophiolitic hinterland.

The studied soils· are remarkably impoverished in clay size fraction and clay minerals as well. This is due to the impeded chemical weathering under the prevailing arid climate. Corroborative techniques including X-ray diffraction, infrared …

Using Environmental Education To Integrate Persons With Mental Illness Into The Community, Kathryn Jean Sandoval

Theses Digitization Project

No abstract provided.

Using Symbolic Dynamical Systems: A Search For Knot Invariants, Russell Clark Wheeler

Theses Digitization Project

No abstract provided.

A Walking Tour For Elementary Students Of The Historical District Of Highland, California, Mary Beth Norris

Theses Digitization Project

No abstract provided.

Environmental Science Curriculum For Eleventh Through Twelfth Grade Classes, Jenelle Sue Bryan

Theses Digitization Project

No abstract provided.

The Auditory Display In Interactive Courseware: Moving Human Factors Into Computer Education, David T. Lauret

CCE Theses and Dissertations

The arrival of inexpensive high fidelity audio capabilities for personal computers has been accompanied by sweeping claims of enhanced educational effectiveness. Research has only served to confuse these claims with both significant and non-significant findings. This may be due partly to the single dimensional model which has been assumed when examining audio. When computer-based audio is examined as a multi-dimensional display analogous in capability and function to the more familiar visual display (computer screen), a different picture emerges. Although it is now clear that integrated audio can enhance learning, the instructional designer is still left with little guidance whether or …

Aerosol Particle Scavenging By Fog And Haze Droplets, Josef Podzimek

Physics Faculty Research & Creative Works

Droplet imprints in thin gelatin layers have been used for the investigation of coarse particles embedded in fog (haze) droplets in comparison to interstitial particles. Droplet samples were taken in less polluted regions of Missouri and Illinois and also in more polluted marine-urban environment in Italy. Considerable differences in particle size distribution and particle location inside the droplets have been found in samples collected on four sampling sites. The deduced relationships can be applied for the description of the aerosol scavenging process in fogs. The pollution of fog (haze) droplets may be related to the droplet mean volume radius and …

Self-Consistent Effective Binary Interaction Approximation For Strongly Coupled Multifluid Dynamics, John D. Ramshaw

Physics Faculty Publications and Presentations

An improved self-consistent effective binary diffusion approximation for multicomponent diffusion was recently described [1]. Here we develop an analogous self-consistent effective binary interaction (SCEBI) approximation for simplifying multifluid dynamical descriptions in which each fluid is strongly coupled to the other fluids by pairwise frictional forces. The net drag force on each fluid is the summation of the drag forces due to each of the other fluids. This summation is approximated by a single term proportional to the velocity of the fluid in question relative to an appropriately weighted average velocity. This approximation permits an explicit numerical solution for the fluid …

Auto Body Surface Coating: A Practical Guide To Reducing Air Emissions, University Of Northern Iowa. Small Business Pollution Prevention Center.

Iowa Waste Reduction Center Book Gallery

No abstract provided.