Physical Sciences and Mathematics Commons^™

A Completely Integrable System And Parametric Representation Of Solutions Of The Wadati-Konno-Ichikawa Hierarchy, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

A finite-dimensional involutive system is presented, and the Wadati-Konno- Ichikawa (WKI) hierarchy of nonlinear evolution equations and their commutator representations are discussed in this article. By this finite-dimensional involutive system, it is proven that under the so-called Bargmann constraint between the potentials and the eigenfunctions, the eigenvalue problem (called the WKI eigenvalue problem) studied by Wadati, Konno, and Ichikawa [J. Phys. Sot. Jpn. 47, 1698 (1979)] is nonlinearized as a completely integrable Hamiltonian system in the Liouville sense. Moreover, the parametric representation of the solution of each equation in the WKI hierarchy is obtained by making use of the solution …

Density Of States Of A Damped Quantum Oscillator, Andreas Hanke, W. Zwerger

Physics & Astronomy Faculty Publications

We calculate the density of states of a damped quantum-mechanical harmonic oscillator which is described by a Caldeira-Leggett type model with Ohmic dissipation and a Drude-like cutoff. From the exact expression for the associated partition function, we derive the asymptotic behavior of the density of states using Tauberian theorems. An effective algorithm to evaluate the density of states is presented and examples are given. It is pointed out that the calculated density of states is an experimentally accessible quantity.

A Hierarchy Of Nonlinear Evolution Equations And Finite-Dimensional Involutive Systems, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

A spectral problem and an associated hierarchy of nonlinear evolution equations are presented in this article. In particular, the reductions of the two representative equations in this hierarchy are given: one is the nonlinear evolution equation rl= - ar,- 2icu/3] r2] r which looks like the nonlinear Schrijdinger equation, the other is the generalized derivative nonlinear Schrijdinger equation rt= $ar,,- ialr12r- a/3(lr12r),- a j3I r I 2r,-2iap21r14r which is just a combination of the nonlinear Schrijdinger equation and two different derivative nonlinear Schrodinger equations [D. J. Kaup and A. C. Newell, J. Math. Phys. 19, 789 (1978); M. J. Ablowitz, …

Supplemental Carbon Dioxide And Light Improved Tomato And Pepper Seedling Growth And Yield, Alejandro Fierro, Nicolas Tremblay, André Gosselin

School of Earth, Environmental, & Marine Sciences Faculty Publications

The experiment was conducted to determine the effects of CO, enrichment (900 μl·liter-1, 8 hours/day) in combination with supplementary lighting of 100 μmol·s-1·m-2 (16- h photoperiod) on tomato (Lycopersicon esculentum Mill.) and sweet pepper (Capsicum annuum L.) seedling growth in the greenhouse and subsequent yield in the field. Enrichment with CO2 and supplementary lighting for » 3 weeks before transplanting increased accumulation of dry matter in shoots by » 50% compared with the control, while root dry weight increased 49% for tomato and 6270 for pepper. Early yields increased by =1570 and 11% for tomato and pepper, respectively.

An Involutive System And Integrable C. Neumann System Associated With The Modified Korteweg-De Vries Hierarchy, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

In this article, a system of finite-dimensional involutive functions is presented and proven to be integrable in the Liouville sense. By using the nonlinearization method, the C. Neumann system associated with the modified Korteweg-de Vries (mKdV) hierarchy is obtained. Thus, the C. Neumann system is shown to be completely integrable via a gauge transformation between it and an integrable Hamiltonian system. Finally, the solution of a stationary mKdV equation and the involutive solutions of the mKdV hierarchy are secured. As two examples, the involutive solutions are given for the mKdV equation: u,+ ;uXXX- $u2u,=0 and the 5th mKdV equation v,- …

Dilaton Black Holes With Electric Charge, Malik Rakhmanov

Physics & Astronomy Faculty Publications

New static spherically symmetric solutions of the Einstein-Maxwell gravity with the dilaton field are found. The solutions correspond to black holes and naked singularities. In addition to mass and electric charge these solutions are labeled by a new parameter, the dilaton charge of the black hole. Depending on the values of electric and dilaton charges there are different types of solutions. The solutions exhibit a new type of a symmetry. Namely one solution transforms into another when the mass and the dilaton charge are interchanged. We also found that there is a finite interval of values of electric charge for …

A New Completely Integrable Liouville's System Produced By The Kaup-Newell Elgenvalue Problem, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

Under the constraint between the potentials and eigenfunctions, the Kaup–Newell eigenvalue problem is nonlinearized as a new completely integrable Hamiltonian system (R2N,dpΛdq,H): H=i〈Λ2p,q〉+1/2〈Λq,q〉〈Λp,p〉. Furthermore, the involutive solution of the high‐order Kaup–Newell equation is obtained. Specifically, the involutive solution of the well‐known derivative Schrödinger equation ut=1/2iuxx+1/2(u‖u‖2)x is developed.

Site Assessment / Initial Remedial Action, Phillips Properties (Mcallen, Tx), Valley Scientific Remediation (Palmview, Tx)

Contaminación Collection

"This report presents the data, analyses, results, and recommendations from the Initial Remedial Actions and Phase II Environmental Site Assessment. This report has been performed by Valley Scientific Remediation, Inc. (VSR) in the last quarter of 1991 and the first quarter of 1992, on behalf of Phillips Properties, Inc. at the Phillips Properties# 1 McAllen facility, located at 2215 West Business Hwy 83, near the southeast corner of Business Highway 83 and 23rd st., McAllen, Texas."

Second-Order Parametrized-Post-Newtonian Lagrangian, Matthew J. Benacquista

Physics & Astronomy Faculty Publications

A many-body Lagrangian to second post-Newtonian order using an extension of the parametrized-post-Newtonian (PPN) formalism is introduced and the properties of new parameters are explored. A parametrized gauge transformation is developed to permit comparison with theories of gravity in a variety of different coordinate systems. A procedure to impose Lorentz invariance on a general second-order post-Newtonian Lagrangian is developed. The Lagrangian is then constrained to possess Lorentz invariance and a "Lorentz-invariant" gauge is introduced. The constrained Lagrangian is found to be described by ten new second-order PPN parameters. When the Lagrangian is further constrained to describe theories of gravity for …

Organochlorine Pesticide Residue, Physico-Chemical, And Bacteriological Profile Of The Lower Rio Grande River Of Texas, Juan H. Gonzalez

Theses and Dissertations - UTB/UTPA

An investigation was conducted to determine if the widespread and abundant use of organochlorine pesticides in the Lower Rio Grande Valley of Texas has had any effect on the microbial flora in the water and in the bottom sediments of the Lower Rio Grande River of Texas.

Rio Grande River water and bottom sediments were cultured for microbial flora, were analyzed for pesticide residues, and the physicochemical properties of the water were determined. Samples were taken at four different sites during a ten month sampling period in 1974.

Traces of organochlorine residues were found in the water, and higher concentrations …

Coastal Vegetational Communities Of The Two Texas Barrier Islands, Boca Chica And Brazos, Baltazar Cisneros

Theses and Dissertations - UTB/UTPA

Two Texas barrier islands, Boca Chica and Brazos, have unique coastal vegetational communities that may be Influenced by several environmental factors. These environmental factors include temperature, precipitation, wind speed, sunshine exposure, day length, and dune height. The purpose of this investigation was to determine the total number of coastal plant species per station, season, and year and to consider environmental factors that may significantly affect the number and pattern of coastal species. Coverage comparison between aerial and land sampling and aerial vegetational zonation was also considered.

Results indicated the presence of 21 angiosperm families and a total of 54 species. …

Plan Of Development For Valley Gravity Project, Julius A. Krug, Michael W. Straus, Wesley R. Nelson

Lower Rio Grande Valley Curated Material

"The Valley Gravity Project Plan has been formulated to furnish an adequate and dependable irrigation water supply for fertile and productive area in the Lower Rio Grande Valley, Texas, It would also provide drainage works, which would remove the threat of destruction of the economy of the area due to effects of a high water table and salt accumulations. The project works would permit generation of the maximum practicable amount of electrical energy which otherwise would be required to operate irrigation pumping plants. Other incidental benefits include fish and wildlife conservation, recreation and flood control."

Project report no. 5-0619-0