Physical Sciences and Mathematics Commons^™

Rotating Disk Flow With Heat Transfer Of A Non Newtonian Fluid In Porous Medium, Hazem Ali Attia

Turkish Journal of Physics

The steady flow of an incompressible viscous non-Newtonian fluid above an infinite rotating disk in a porous medium is studied with heat transfer. Numerical solutions of the nonlinear differential equations which govern the hydrodynamics and energy transfer are obtained. The effect of the porosity of the medium and the characteristics of the non-Newtonian fluid on the velocity and temperature distributions is considered.

Ramifications Of Lineland, Daniel Grumiller, Rene Meyer

Turkish Journal of Physics

A non-technical overview on gravity in two dimensions is provided. Applications discussed in this work comprise 2D type 0A/0B string theory, Black Hole evaporation/thermodynamics, toy models for quantum gravity, for numerical General Relativity in the context of critical collapse and for solid state analogues of Black Holes. Mathematical relations to integrable models, non-linear gauge theories, Poisson-sigma models, KdV surfaces and non-commutative geometry are presented.

Charges In Ads Spacetimes, İbrahi̇m Güllü, Bayram Teki̇n

Turkish Journal of Physics

We give a review of our recent work on conserved charges in cosmological spacetimes. We compute the mass and the angular momenta of various solutions in D dimensions. This is an extended version of a talk given by B. Tekin. The original material can be found in the related papers in our references.

Bis([Mu]-Thio­Phene-2-Carbaldehyde Thio­Semicarbazonato)Bis­[Acetonitrile­Copper(I)] Bis­(Tetra­Fluoro­Borate), Robert D. Pike, Austin B. Wiles, Tristan A. Tronic

Arts & Sciences Articles

The title compound, [Cu2(C6H7N3S2)2(C2H3N)2](BF4)2, is a dimer with a central Cu2S2 core resulting from thio­semi­carbazone sulfur bridging. Both Cu-TCT units (TCT is the thio­phene-2-carboxaldehyde thio­semicarbazone anion) are roughly planar and are parallel to one another and perpendicular to the Cu2S2 plane.

You Should Run For Office (Video), Kevin O'Brien, Grace Drake

All Maxine Goodman Levin School of Urban Affairs Publications

No abstract provided.

Using The Census Bureau's Public Use Microdata For Migration Analysis, Mark Salling, Ellen Cyran

All Maxine Goodman Levin School of Urban Affairs Publications

Using the Census Bureau's Public Use Microdata for Migration Analysis, Proceedings of the annual conference of the Urban and Regional Information Systems Association, Vancouver, BC, Canada, September 2006, pp.336-348.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 4, January 2006, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Preface, Djamal Benslimane, Chirine Ghedira, Zakaria Maamar

All Works

No abstract provided.

Handling The Subclassing Anomaly With Object Teams, Jeff Furlong, Atanas Radenski

Mathematics, Physics, and Computer Science Faculty Articles and Research

Existing Java software or libraries can evolve via subclassing. Unfortunately, subclassing may not properly support code adaptation when there are dependencies between classes. More precisely, subclassing in collections of related classes may require reimplementation of otherwise valid classes. This problem is defined as the subclassing anomaly, which is an issue when software evolution or code reuse is a goal of the programmer who is using existing classes. Object Teams offers an implicit fix to this problem and is largely compatible with the existing JVM’s. In this paper, we evaluate how well Object Teams succeeds in providing a solution for a …

The "Fair" Triathlon: Equating Standard Deviations Using Bayesian Nonlinear Models, Gilbert W. Fellingham, C. Shane Reese, S. Mckay Curtis

Faculty Publications

The Ironman triathlon was created in 1978 by combining events with the longest distances for races then contested in Hawaii in swimming, cycling, and running. The Half Ironman triathlon was formed using half the distances of each of the events in the Ironman. The Olympic distance triathlon was created by combining events with the longest distances for races sanctioned by the major federations for swimming, cycling, and running. The relative importance of each event in overall race outcome was not given consideration when determining the distances of each of the races in modern triathlons. Thus, there is a general belief …

Mathematically Modeling The Effects Of Counting Factor (Cf) In Dictyostelium Discoideum, J. C. Dallon, W. Jang, R. H. Gomer

Faculty Publications

Size regulation is a crucial feature in many biological systems, with misregulation leading to dysplasia or hyperplasia. The recent discovery of counting factor (CF) in Dictyostelium discoideum will lead to a greater understanding of how the system regulates the size of a group of cells. In this paper we mathematically model the known effects of CF using two different models: a cellular automata model and a discrete continuum hybrid model. With the use of these models we are able to understand how modulation of adhesion and motile forces by CF can facilitate stream breakup. In addition, the modelling suggests a …

Neural Network-Based Output Feedback Controller For Lean Operation Of Spark Ignition Engines, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier, Jonathan B. Vance, Pingan He

Electrical and Computer Engineering Faculty Research & Creative Works

Spark ignition (SI) engines running at very lean conditions demonstrate significant nonlinear behavior by exhibiting cycle-to-cycle dispersion of heat release even though such operation can significantly reduce NOx emissions and improve fuel efficiency by as much as 5-10%. A suite of neural network (NN) controller without and with reinforcement learning employing output feedback has shown ability to reduce the nonlinear cyclic dispersion observed under lean operating conditions. The neural network controllers consists of three NN: a) A NN observer to estimate the states of the engine such as total fuel and air; b) a second NN for generating virtual input; …

Point Of Care Healthcare Quality Control For Patients Using Mobile Devices, Owen Lynch

Masters

The advances made in the domain of mobile telecommunications over the last decade offer great potential for developments in many areas. One such area that can benefit from mobile communications is telemedicine, which is the provision of medical assistance, in one form or another, to patients who are geographically separated from the healthcare provider. When a person is ill, individual attention from medical professionals is of the utmost importance until they have returned to full health. However, people who suffer with long term and chronic illnesses may need life long care and often must manage their condition at home. Many …

Solubilisation, Purification And Processing Of Single Walled Carbon Nanotubes Using Organic Molecules, Theresa Hedderman

Doctoral

The aims of this research are seven fold; • To enhance the solubility of SWNTs in organic solvents. • To purify an untreated sample of SWNTs that contains many side products. • To gain a greater understanding of the interaction between the polycyclic aromatic hydrocarbons and SWNTs. • To debundle and disperse SWNTs. • To select SWNTs of a specific structure based on the structures of the polycyclic aromatic hydrocarbons used. • To observe and compare the interaction of polycyclic aromatic hydrocarbons with SWNTs produced by different methods. • To elucidate factors which contribute to different degrees of interaction between …

Effects Of Novel Synthetic Nucleosides As Anti-Tumor Agents On Human Acute Promyelocytic Leukemia Cell Line (Hl-60), Salma Awad Merghani Mahmoud

Theses

Nucleosides and their analogs are considered a clinically proven class of therapeutic agents possessing anticancer and antiviral activity. Several trifluoromethyl-substituted pyrazole N-nucleosides (coded NIA, NIIA and NIIA) and their nucleobases were synthesized and tested for the ability to induce apoptosis in acute human promyelocytic cell line (HL-60). The growth and proliferation of HL-60 was more effectively inhibited by NIA, NIIA and their nucleobases compared to NIIIA and its nucleobase. In addition, DNA fragmentation was detected in a concentration-dependent manner as a result of nucleosides treatment. A caspase-3-dependent apoptosis was observed based on the Western blot analysis of poly-ADP-ribose polymerase (PARP) …

Assessment Of The Effectiveness Of Available Pollution Control Technologies In Reducing Phenol Level At Enoc Refinery Wastewater Treatment Plant, Waddah Shihab Ghanim Al Hashemi

Theses

Phenols are present in discharge effluents of many heavy industries such as refineries. They are regulated and monitored by environmental authorities. Emirates National Oil Company (ENOC) processes condensate oil and produces wastewater that is treated at the ENOC Processing Company's (EPCL-refinery) wastewater treatment plant (ETP) through the use of physical, chemical and biological treatment processes. This study provides an in-depth description of the unit processes employed to treat the different waste streams generated at the EPCL refinery and identifies the different types of phenols which are formulated in the processes. Characterization of phenol level at EPCL-ETP and assessment of the …

The Sedimentary Environment Below Earth’S Polar Ice Cap As A Microbial Habitat, David C. Smith, Stephanie Forschner-Dancause, David C. Rowley, Steven D'Hondt

Graduate School of Oceanography Faculty Publications

University of Rhode Island faculty participated in drilling of the polar ice cap to study microbial diversity and adaptation to subsurface life under conditions that may mimic extraterrestrial subsurface conditions.

Synthesis Of Some Pyridinone Nucleoside Analogues As Antitumor Agents, Shaikha Saif Saeed Alneyadi

Theses

Abstract

3-Deazapyrimidine nucleosides have been shown to exhibit great potential as pro drug for use in medicine especially as antagonists to cancer tumors and the HIV-virus. Recent research has focused on the design, synthesis and characterization of novel nucleoside analogues.

Fluoropyridinone and their corresponding nucleoside derivatives have been synthesized and characterized to induce the activity against tumors. 4, 6-diaryl-3-cyano-2(1H)-pyridinones (82a-i) and their nucleosides were prepared. A trifluoromethyl group was introduced into the pyridinone ring system to study its effect on different tumor cells. The glycoside analogues (83a-e, 85a-e, 87a-e and 88a-d) have been synthesized …

Development Of Electroanalytical Methods For The Determination Of Sialic Acid As A Biomarker For Cancer, Khawla Ali Rashid Al-Tayyari

Theses

Sialic acid (SA) is a general term for a family composed of 43 derivatives of neuraminic acid. Whereas N-acetylneuraminic acid (NANA) is the most commonly occurring sialic acid in human. There has been a great interest in the determination of SA in humans because variations in SA level was linked to different medical conditions and diseases. In particular, serum SA are elevated in several types of cancers. SA also exists in Erythropoietin (EPO), a hormone, which induces the production of red blood cells and hence used in the treatment of anemia.

Although of the great physiological significance of SA …

Effects Of Medicinal Plants On Lead Induced Toxicity Of Biotransformation And Redox Cycling Enzymes, Yusra Saif Khalfan Al Dhaheri

Theses

All organisms including humans are constantly and unavoidably exposed to foreign chemicals (xenobiotics), which include both manufactured and natural molecules such as pollutants and plant metabolites. One such alarming pollutant is lead as it is constantly produced from automobiles exhaust products and food containers. It has been documented that lead, as the major heavy metal pollutant in the air, has notable effects on nervous systems and efficiency of several enzymes.

There are some natural products such as medicinal plants that might have antagonistic effects against such pollutants. Several medicinal plants are used as traditional remedies for many ailments without knowing …

Proximity In Context: An Empirically Grounded Computational Model Of Proximity For Processing Topological Spatial Expression., John D. Kelleher, Geert-Jan Kruijff, Fintan Costello

Conference papers

The paper presents a new model for context-dependent interpretation of linguistic expressions about spatial proximity between objects in a natural scene. The paper discusses novel psycholinguistic experimental data that tests and verifies the model. The model has been implemented, and enables a conversational robot to identify objects in a scene through topological spatial relations (e.g. ''X near Y''). The model can help motivate the choice between topological and projective prepositions.

A Computational Model Of The Referential Semantics Of Projective Prepositions, John D. Kelleher, Josef Van Genabith

Conference papers

In this paper we present a framework for interpreting locative expressions containing the prepositions in front of and behind. These prepositions have different semantics in the viewer-centred and intrinsic frames of reference (Vandeloise, 1991). We define a model of their semantics in each frame of reference. The basis of these models is a novel parameterized continuum function that creates a 3-D spatial template. In the intrinsic frame of reference the origin used by the continuum function is assumed to be known a priori and object occlusion does not impact on the applicability rating of a point in the spatial template. …

Electronic Counting Rules For The Stability Of Metal-Silicon Clusters, J. Ulises Reveles, Shiv N. Khanna

Physics Publications

First principles electronic structure calculations have been carried out to examine the stability of cationic, neutral, and anionic MSi15, MSi16, and MSi17 (M=Sc, Ti, and V) clusters. ScSi16−, TiSi16, and VSi16+ are found to be particularly stable in agreement with recent experiments. It is shown that the enhanced stability can be reconciled within a model where each Si atom coordinated to the metal contributes one electron to the valence pool. Clusters where the total number of valence electrons obtained by summing one electron from each Si site coordinated to metal atom and the valence electrons of the metal attain 20 …

Ferromagnetism In Al1−Xcrxn Thin Films By Density Functional Calculations, Q. Wang, A. K. Kandalam, Q. Sun, Puru Jena

Physics Publications

We report the results of a theoretical study of magnetic coupling between Cr atoms doped in bulk AlN as well as AlN (112¯0) thin films having wurtzite structure. The calculations are based on density fuctional theory with the generalized gradient approximation to the exchange and correlation potential. In the thin film, modeled by a slab of finite thickness, Cr atoms are found to cluster around N on the surface layer and couple ferromagnetically. The results for the Cr-doped AlN crystal are similar, namely, Cr atoms cluster around N and couple ferromagnetically. In the thin film, the preference of Cr to …

Dehydrogenation Mechanism In Catalyst-Activated Mgh2, S. Li, Puru Jena, R. Ahuja

Physics Publications

A small amount of Nb2O5 catalyst is known to substantially improve the desorption thermodynamics and kinetics of MgH2. Using density functional theory in combination with ab initio molecular dynamics simulation, we provide theoretical understanding of the mechanism of dehydrogenation in Nb doped MgH2. We show that the substitution of Nb at the Mg site followed by the clustering of H around Nb is a likely pathway for hydrogen desorption. We also find that dehydrogenation from the vicinity of Mg vacancies is exothermic. However, the vacancies are not likely to play a significant role in hydrogen desorption due to their high …

Strong Suppression Of The Yellow Luminescence In C-Doped Gan In Air Ambient, Michael A. Reshchikov

Physics Publications

The authors observed a drastic reduction of the yellow luminescence (YL) intensity in carbon-doped semi-insulating GaN in air or oxygen ambient as compared to the intensity in vacuum. The YL intensity dropped about 300 times while the exciton emission remained almost unchanged. The authors assume that the donor-acceptor-pair transitions involving a gallium vacancy complex in a thin near-surface region cause the strong YL. Oxygen molecules or ions induce the surface states acting as a very efficient channel of nonradiative recombination. The results indicate that carbon may not be involved in the acceptor responsible for the YL band in GaN:C.

Determination Of Acceptor Concentration In Gan From Photoluminescence, Michael A. Reshchikov

Physics Publications

The concentration of the acceptor responsible for the yellow luminescence (YL) band at about 2.2eV in GaN is determined from photoluminescence. The YL band intensity increases linearly with excitation power density and partially saturates above some critical value. The dependence is quantitatively described within a phenomenological model accounting for recombination statistics in GaN layer and saturation of acceptors with photogenerated holes. The incomplete saturation of the YL intensity at high excitation intensities is explained by gradual saturation of acceptors at different distances from the sample surface. The identity of deep and shallow acceptors in GaN is discussed.

Midinfrared Intersubband Absorption In Znxcd1−Xse/Znx′Cdy′Mg1−X′−Y′Se Multiple Quantum Well Structures, H. Lu, A. Shen, M. C. Tamargo, C. Y. Song, H. C. Liu, S. K. Zhang, R. R. Alfano, M. Muñoz

Physics Publications

The authors report the observation of intersubband absorption in ZnxCd(1−x)Se/Znx′Cdy′Mg(1−x′−y′)Semultiple quantum wells. Lattice-matched samples were grown by molecular beam epitaxy on InP (001) substrates. Photoluminescence measurements indicate that the samples have excellent material quality. The peak absorption wavelengths measured by Fourier transform infrared spectroscopy are 3.99 and 5.35μm for two samples with ZnxCd(1−x)Se well widths of 28 and 42Å, respectively. These values fall within the 3–5μm wavelength range, which is of interest for midinfrared intersubband devices, such as quantum cascade lasers and quantum well infrared photodetectors. Their experimental results fit well with theoretical predictions based on the envelope function approximation. …

South Florida Coastal Water Quality Monitoring Network Fy2006 Cumulative Report To The South Florida Water Management District (Contract No. C-15397 And 4600000352), Joseph N. Boyer, Henry O. Briceño

SERC Research Reports

No abstract provided.

2006 Annual Report Of The Water Quality Monitoring Project For The Water Quality Protection Program Of The Florida Keys National Marine Sanctuary, Joseph N. Boyer, Henry O. Briceño

SERC Research Reports

No abstract provided.