Physical Sciences and Mathematics Commons^™

A Theoretical Model For The Non-Linear Susceptibility Of The Antiferromagnetic Systems, Beki̇r Özçeli̇k, Keri̇m Kiymaç, Ahmet Eki̇ci̇bi̇l

Turkish Journal of Physics

In this study, we have developed a general theoretical model, based upon the simple mean field model of N\'{e}el, for the non-linear response of an antiferromagnetic system. The results indicate that the odd order derivatives, (d^{2n + 1}m_{a})_{0} = (-d^{2n + 1}m_{b})_{0}, where n=1,2,3......, will diverge and the even order derivatives, (d^{2n}m_{a})_{0} = (d^{2n}m_{b})_{0} will vanish due to the symmetry of two sublattices, ``a'' and ``b'', forming the antiferromagnet. This model also supports our experimental results performed on two antiferromagnetic samples, namely, Cs_{2}MnCl_{4}.2H_{2}O and MnCl_{2}.4H_{2}O [1].

Reliability Studies Of The Skew Normal Distribution, Nicole Dawn Brown

Electronic Theses and Dissertations

It has been observed in various practical applications that data do not conform to the normal distribution, which is symmetric with no skewness. The skew normal distribution proposed by Azzalini(1985) is appropriate for the analysis of data which is unimodal but exhibits some skewness. The skew normal distribution includes the normal distribution as a special case where the skewness parameter is zero. In this thesis, we study the structural properties of the skew normal distribution, with an emphasis on the reliability properties of the model. More specifically, we obtain the failure rate, the mean residual life function, and the reliability …

Ichnology Of Holocene Carbonate Eolianites Of The Bahamas, H. Allen Curran, Brian White

Geosciences: Faculty Publications

No abstract provided.

A Sea-Level Lowstand (Devil's Point Event) Recorded In Bahamian Reefs: Comparison With Other Last Interglacial Climate Proxies, Brian White, H. Allen Curran, Mark A. Wilson

Geosciences: Faculty Publications

Reprinted from: Benjamin J. Greenstein and Cindy K. Carney (eds.) Proceedings of the 10th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Gerace Research Center

Resilience And Recovery Of Coral Reefs From Large-Scale Disturbances: Contrasting Patterns For San Salvador Island, Bahamas, And Belize, Paulette M. Peckol, H. Allen Curran, Martha Robbart, Benjamin J. Greenstein

Geosciences: Faculty Publications

Benjamin J. Greenstein and Cindy K. Carney (eds)

San Salvador, Gerace Research Center

Coastal Effects Of Hurricane Floyd On San Salvador Island, Bahamas, H. Allen Curran, Priscilla Delano, Brian White, Meredith Barrett

Geosciences: Faculty Publications

Hurricane Floyd, a Category 4 storm with winds up to I 55 mph, made a close encounter with San Salvador Island on September 13-14, 1999. In addition to inflicting severe damage to homes, tourist facilities, businesses, and infrastructure on the island, the storm also caused considerable beach erosion and coastal modification, mostly on the western and northern coasts. This paper reports and documents with photos the findings of a survey of coastal erosion effects on four areas of the San Salvador coastline: Coast Guard Beach, Rocky Point south to Cockburn Town and Fernandez Bay, South of Sugarloaf toward Grotto Bay, …

Impedance Feedback Control For Scanning Electrochemical Microscopy, David O. Wipf, Mario A. Apuche-Avlles

College of Arts and Sciences Publications and Scholarship

A new constant-distance imaging method based on the relationship between tip impedance and tip-substrate separation has been developed for the scanning electrochemical microscope (SECM). The tip impedance is monitored by application of a high frequency ac voltage bias between the tip and auxiliary electrode. The high frequency ac current is easily separated from the dc level faradaic electrochemistry with a simple RC filter, which allows impedance measurements during feedback or generation/collection experiments. By employing a piezo-based feedback controller we are able to maintain the impedance at a constant value and, thus, maintain a constant tip-substrate separation. Application of the method …

Thermodynamic Properties Of Neutron-Rich Matter, Matt Tilley, Bao-An Li

Journal of the Arkansas Academy of Science

The mechanism of supernova explosion and properties of neutron stars are uniquely determined by the equation of state of neutron-rich matter. Using a phenomenological equation of state within a thermal model, we study thermodynamic properties of neutron-rich matter. In particular, we investigate chemical (diffusive) and mechanical (isothermal) instabilities of neutron-rich matter and their dependence on the nuclear equation of state. Both instabilities are found to be heavily dependent upon the isospin asymmetry, temperature, and density of neutron-rich matter. We show that the boundary of the chemical instability extends farther out into the density-isospin symmetry plane than that of the mechanical …

Moisture Determination By Thermal Titrimetry Using The Enthalpy Of Reaction Of 2,2-Dimethoxypropane With Water, Edmond W. Wilson Jr., Reagan Baber

Journal of the Arkansas Academy of Science

Assays for water content can be readily and simply carried out using the technique of thermal titrations. The method is based on measuring the endothermic heat of reaction exhibited when 2,2-dimethoxypropane is brought into contact with water in the presence of an acid catalyst. The apparatus is simple, requiring a constant delivery rate buret, a recording thermistor thermometer, and a stirred, thermally insulated reaction container. The 2,2-dimethoxypropane reagent used for the water assays is environmentally friendly ("green"). It is stable, pleasant smelling and economical. Working curves in three solvents, acetonitrile, tetrahydrofuran and 1,4-dioxane, show excellent precision and linearity with increasing …

Plasmid Analysis Of Bacteria That Metabolize The Detergent Igepon, Russell O. Nordeen, Thetsu Mon, David Gilmore

Journal of the Arkansas Academy of Science

No abstract provided.

Effects Of Humic Acids And Salinity On Pesticide Bioavailability And Toxicity As Estimated By Spme And Toxicity Tests, Laurent C. Mézin

Dissertations, Theses, and Masters Projects

The interactive effects of humic acids (HAs) and salinity on the bioavailability and toxicity of the pesticides chlorpyrifos and 4,4'-dichlorodiphenyltrichloroethane (DDT) were investigated. The effects of various HAs on the toxicity of chlorpyrifos were initially assessed with the chronic MicrotoxRTM test. Environmentally relevant concentrations of Aldrich, Peat, Leonardite and Suwannee River HAs had no significant effect on the toxicity of either chlorpyrifos or copper (Cu), the test's positive control. as reductions in contaminant toxicity had previously been reported for some contaminants by HAs, it appeared that salinity might be a mitigating factor. Thus salinity effects were further investigated with Aldrich …

Meso-1, 2-Bis (Methylazo)-1, 2-Diphenylethane, Craig A. Bayse, Barry K. Carpenter, Rudy L. Luck

Chemistry & Biochemistry Faculty Publications

The title compound, meso-1,2-bis(methyldiazenyl)-1,2-diphenylethane, C16H18N4, is arranged in a disordered manner around an inversion point. The N—N atom distances in the azo group of 1.192 (8) and 1.195 (8) Å, and the C—C atom distances in the ethylene moiety at 1.512 (8) and 1.503 (8) Å in the two models [refined to 51.7 (6) and 48.3 (6)% occupancies] were not significantly different.

Yield-Per-Recruit Analysis For Black Drum, Pogonias Cromis, Along The East Coast Of The United States And Management Strategies For Chesapeake Bay, Cynthia M. Jones, Brian K. Wells

OES Faculty Publications

Black drum, Pogonias cromis along the U.S. East Coast is subject to commercial and recreational harvest. However, prior to this study no modeling had been undertaken to examine the potential for overfishing in the Chesapeake Bay region. We present evidence from yield-per-recruit models that growth overfishing of black drum is unlikely under current fishing practices in this region. Particular attention was given to fishing practices in the Chesapeake Bay region where old, large fish predominate in the commercial and recreational catches (mean age=26 years: mean total length=108.4 cm; mean weight 22.1 kg). Yield-per-recruit model results showed that growth overfishing was …

The 6th International Conference And Workshop On Lobster Biology And Management: An Introduction, Mark J. Butler Iv

Biological Sciences Faculty Publications

Every three years or so, the International Conference and Workshop on Lobster Biology and Management (ICWL) brings together lobster scientists, fishery managers, and industry representatives from around the world for a week of scientific presentations, workshops, and discussions on lobster biology and management. The first ICWL was held in Perth, Australia, in January 1977. Its purpose was to bring together a small group of lobster researchers from the USA and Australia to discuss common issues and themes. That initial workshop spawned a continuing series of meetings that have become the international lobster conference for scientists—the equivalent of an international congress …

Seasonal Climatology Of Hydrographic Conditions In The Upwelling Region Off Northern Chile, J. L. Blanco, A. C. Thomas, M.-E. Carr, P. T. Strub

OES Faculty Publications

Over 30 years of hydrographic data from the northern Chile (18°S-24°S) upwelling region are used to calculate the surface and subsurface seasonal climatology extending 400 km offshore. The data are interpolated to a grid with sufficient spatial resolution to preserve crossshelf gradients and then presented as means within four seasons: austral winter (JulySeptember), spring (October-December), summer (January-March), and fall (April-June). Climatological monthly wind forcing, surface temperature, and sea level from three coastal stations indicate equatorward (upwelling favorable) winds throughout the year, weakest in the north. Seasonal maximum alongshore wind stress is in late spring and summer (DecemberMarch). Major water masses …

Evaluation Of In Situ Bioremediation Approaches In Meeting International Standards For Organic And Residual Metals Toxicity In Soils, Jason Allan Mcdonald

LSU Master's Theses

Drilling fluids and muds are an essential component of the rotary drilling process used to drill for oil and gas on land and in offshore environments. However, the bioaccumulation of petroleum contaminated soils/drilling mud due to oil and natural gas exploration has posed a major environmental concern due to its prolonged environmental persistence and its leachability below the rhizosphere. The main objectives of this research were: (i) To assess initial toxicity of drilling mud and related contaminated soils from an agricultural setting in Galliano, Sicily (Phase one) and (ii) To develop a low intervention bioremediation approach using bioplug technology to …

Symplectic Maps To Projective Spaces And Symplectic Invariants, Denis Auroux

Turkish Journal of Mathematics

After reviewing recent results on symplectic Lefschetz pencils and symplectic branched covers of \CP^2, we describe a new construction of maps from symplectic manifolds of any dimension to \CP^2 and the associated monodromy invariants. We also show that a dimensional induction process makes it possible to describe any compact symplectic manifold by a series of words in braid groups and a word in a symmetric group.

The Topology Of Symplectic Manifolds, Robert E. Gompf

Turkish Journal of Mathematics

A topological structure is introduced that seems likely to provide a complete topological characterization of compact symplectic manifolds. The article begins with a leisurely introduction to symplectic manifolds from a topological viewpoint. It then focuses on Thurston's construction of a symplectic structure on the total space of a fiber bundle. This is generalized to a technique for putting a symplectic structure on the domain of a J-holomorphic map. A topological structure called a hyperpencil on a compact 2n-manifold is then defined; this is motivated by the special case of a linear system of curves on an algebraic manifold, and it …

Surface Bundles: Some Interesting Examples, Jim Bryan, Ron Donagi, Andras I. Stipsicz

Turkish Journal of Mathematics

We show two constructions of surface bundles over Riemann surfaces admitting nonvanishing signatures.

Torus Fibrations On Symplectic Four-Manifolds, Ivan Smith

Turkish Journal of Mathematics

This paper has two essentially unrelated halves. In the first we prove that a closed symplectic four-manifold admitting a fibration by connected, homologically essential Lagrangian tori with "tame" singularities, is fibre-preserving diffeomorphic to a K3 surface or to a torus bundle over a torus with first Betti number at least three. In the second, we prove that these torus bundles over tori admit Lefschetz pencils by genus three curves. It follows that the genus three mapping class group admits infinitely many inequivalent irreducible positive relations. Motivations for the questions are provided from mirror symmetry, integrable systems and Seiberg-Witten theory: in …

Floer Homology And Its Continuity For Non-Compact Lagrangian Submanifolds, Yong-Geum Oh

Turkish Journal of Mathematics

We give a construction of the Floer homology of the pair of vnon-compact Lagrangian submanifolds, which satisfies natural continuity property under the Hamiltonian isotopy that moves the infinity but leaves the intersection set of the pair compact. This construction uses the concept of Lagrangian cobordism and certain singular Lagrangian submanifolds. We apply this construction to conormal bundles (or varieties) in the cotangent bundle, and relate it to a conjecture made by MacPherson on the intersection theory of the characteristic Lagrangian cycles associated to the perverse sheaves constructible to a complex stratification on the complex algebraic manifold.

A Partial Order On The Group Of Contactomorphisms Of $\R^{2n+1}$ Via Generating Functions, Mohan Bhupal

Turkish Journal of Mathematics

In this note we construct a nontrivial partial order on the identity component of the group of compactly supported contactomorphisms of \R^{2n+1} using the method of generating functions. Our construction is in the framework of the theory developed by Viterbo in the paper \cite{V} wherein, among other things, he showed how one could use generating functions to construct a partial order on the group of compactly supported Hamiltonian symplectomorphisms of \R^{2n}.

Knotting Of Algebraic Curves In Complex Surfaces, Sergey Finashin

Turkish Journal of Mathematics

For any d\ge 5, I constructed infinitely many pairwise smoothly non-equivalent surfaces F\subset\Cp{2} homeomorphic to a non-singular algebraic curve of degree d, realizing the same homology class as such a curve and having abelian fundamental group \pi_1(\Cp2\stmin F). It is a special case of a more general theorem, which concerns for instance those algebraic curves, A, in a simply connected algebraic surface, X, which admit irreducible degenerations to a curve A_0, with a unique singularity of the type X_9, and such that A\cite A>16.

Topological Quantum Field Theory And Hyperkähler Geometry, Justin Sawon

Turkish Journal of Mathematics

Rozansky and Witten proposed a 3-dimensional sigma-model whose target space is a hyperkähler manifold. They conjectured that this theory has an associated TQFT, with vector spaces given by certain cohomology groups of the hyperkähler manifold. On the other hand, there is a certain modified TQFT constructed by Murakami and Ohtsuki using the universal quantum invariant. We explain how the Rozansky-Witten TQFT can be obtained from the latter by applying a "hyperkähler weight system".

Induced Cat^1-Groups, Murat Alp

Turkish Journal of Mathematics

In this paper we define the pullback cat^1-group and show that this Pullback has a right adjoint which is the induced cat^1-group. Later we show that this right adjoint is a pushout of category of cat^1-groups. We calculate the Peiffer subgroups to find a finite group of the source of induced cat^1-groups. The generating set of Peiffer subgroups are also given in this paper. All results are corrected by a GAP[13] program package in [4]. This paper also contains the some computational examples which are the calculation-induced cat^1-group and comparative times between the induced crossed modules and induced cat^1-groups.

P -Banach Algebras With Generalized Involution And C^*-Algebra Structure, Abdellah El Kinani, Aziz Ifzarne, Mohamed Oudadess

Turkish Journal of Mathematics

In this paper, we consider p-Banach algebras endowed with a generalized involution. We show that various C^*-like conditions force the algebra to be C^*-algebra under an equivalent norm.

Inequalities For The Vibrating Clamped Plate Problem, Kimberley Mchale, Ünal Ufuktepe

Turkish Journal of Mathematics

We study the eigenvalues of the vibrating clamped plate problem. We have made improvements on the bounds of the ratios of the eigenvalues of the biharmonic operator (clamped plate) using the methods of Payne, Polya, and Weinberger. The difference in our proof lies mainly with the trial functions and the orthogonality arguments. While Payne, Polya, and Weinberger and Hile and Yeh project away components along u_1,u_2,...,u_k to meet the orthogonality conditions,we use a translation/rotation argument to meet these conditions.

A Perturbed Version Of The Ostrowski Inequality For Twice Differentiable Mappings, A. Sofo, S. S. Dragomir

Turkish Journal of Mathematics

A generalisation of a perturbed version of the Ostrowski inequality for twice differentiable mappings is studied. It is shown that the error bounds are better than those obtained previously. Applications for general quadrature formulae are also given.

On The L^P Solutions Of Dilation Equations, İbrahi̇m Kirat

Turkish Journal of Mathematics

In this paper, the concepts concerning the space of constant breadth were extended to E^n-space. An approximate solution of the equation system which belongs to this curve was obtained. Using this solution vectorial expression of the curves of constant breadth was obtained. The relation \int_0^{2\pi}\widetilde{f}(s)\,ds=0 between the curvatures of curves of constant breadth in E^n was obtained. Key Words and Phrases: Curvature, Constant Breadth, Integral Characterization of Curve"> MathJax.Hub.Config({tex2jax: {inlineMath: [['$','$'], ['\\(','\\)']], displayMath: [['\\[','\\]'], ['$$','$$']]}}); Academic Journals Find Manuscript Copyright Release Form Copyright Release Form(Turkey) Copyright Release Form(Other Countries) Manuscript Submission and Evaluation System On the L^p Solutions of Dilation …

Some Characterization Of Curves Of Constant Breadth In E^N Space, Zülfi̇gar Akdoğan, Abdullah Mağden

Turkish Journal of Mathematics

In this paper, the concepts concerning the space of constant breadth were extended to E^n-space. An approximate solution of the equation system which belongs to this curve was obtained. Using this solution vectorial expression of the curves of constant breadth was obtained. The relation \int_0^{2\pi}\widetilde{f}(s)ds=0 between the curvatures of curves of constant breadth in E^n was obtained. Key Words and Phrases: Curvature, Constant Breadth, Integral Characterization of Curve