Physical Sciences and Mathematics Commons^™

The Use Of Raman Spectroscopy In The Characterization Of Single Walled Carbon Nanotubes, Elizabeth Gregan

Doctoral

Carbon nanotubes, long, thin cylinders of carbon are intriguing structures and
have sparked much excitement in recent years. It is clear that understanding the fundamental properties of nanotubes is necessary to get a realisation of the full potential of these materials. Processing and purification on a mass scale will need to be carried out if these materials are to have large scale industrial applications and move beyond the laboratory bench. Highly sensitive, capital intensive equipment such as TEM and AFM, have been used to identify the state and morphology of tube samples as well as their levels of purity, however …

To Publish Or Not To Publish?- That Is The (Editorial) Question, Bharath Sriraman

The Mathematics Enthusiast

No abstract provided.

Statistics Teaching In An Agricultural University: A Motivation Problem, Klara Lokos Toth

The Mathematics Enthusiast

There are many teaching methods and there are various teaching materials even in one university, not to mention different universities specialising in different disciplines. So I cannot talk about Hungarian method in general, but about my experience in teaching statistics. I teach statistics on several levels (BSc, MSc, PhD) and in different faculties (Agriculture and environmental Sciences, Economic and Social Sciences) and in different forms. I find different problems according to the faculties and forms. In this paper I focus on only one of them, which is the most important for me.

Catch Me If You Can!, Steve Humble

The Mathematics Enthusiast

Learning mathematics outside the classroom is not enrichment, it is at the core of empowering an individuals understanding of the subject.

The three activities described in this article can all be used outside the classroom in a maths lesson. Teaching mathematical concepts in this way engages and reinforces learning. It puts the ideas learnt into a setting and allows time for those ideas to be developed without any of the maths hang-ups which can occur in the classroom. By taking maths beyond the classroom, we can more clearly illustrate the connections between the real world and what they are studying …

Polymeric Nanofibrous Media For Enhanced Ground Water Filtration, Bothaina Abdulla Al Shamsi

Theses

Water is one of the bulk transportation media for transmission of particulate contaminants. These contaminants are complex mixtures of particles; most of them are usually smaller than 1000 µm in diameter. Chemical and biological aerosols (particulates) are frequently in the range of 1- 10 µm. The particulate matters may carry some adsorbed gaseous contaminants. The removal of particulate and biological contaminants is thus an important step in water purification process. Particulate contaminants if not removed tend to foul reverse osmosis membranes and severely reduce the throughput of the final purification step. The filtration industry is looking for more efficient high …

Screening For Latent Or Silent Celiac Disease “Gluten-Sensitive Enteropathy” In Uae Adults Nationals, Waheeba Salman Al Zaabi

Theses

No abstract provided.

Antibiotic Resistance Of Helicobacter Pylori Strains In The United Arab Emirates And Its Relation To The Gene Associated To Gastric Cancer “Cag A Gene”, Wafa Ali Rashid Al-Tayyari

Theses

Helicobacter pylori is a flagellated corkscrew, slow growing neutrophilic gram negative ureolytic organism. It has an extraordinary ability to establish infection in human stomach that can last for years or decades. Its eradication remains an important public health challenge especially in light of broadening indications and increasing antimicrobial resistance.

AIM: i) Identification of H. pylori in UAE patients ii) Determination of the prevalence of antibiotic resistance genes (mutation in 23S rRNA gene in clarithromycin, and deletion in RdxA gene in metronidazole) among H. pylori strains isolated from U.A.E patients by using molecular methods, iii) Ascertain whether Cag A- positive H. …

Workplace Privacy: An Environmental-Behaviour Analysis Of Etisalat Offices In Al-Ain, Latefa Ali Saleh Ahmad Alkuwaiti

Theses

The purpose of this study was to explore environmental quality factors in the workplace and to examine the level of job satisfaction among the employees of Etisalat Al-Ain through three main factors: visual privacy, acoustical privacy and social interaction. The theoretical and conceptual elements of the study evolved from the literature of office history, behaviour studies, building performance evaluation and job satisfaction.

Data were gathered in two stages, first phase with a population of 10 and second stage with 100 subjects of Etisalat employees, including both those working in open plan workstations and those who work in enclosed offices.

Using …

The Germination Ecology And Composition Of The Indigenous Seeds Of Cyprus Conglomeratus: A Sand Dune Binder, Sheikha Saeed Amer Al Neyadi

Theses

Cyperus conglomeratus is among few species that tolerate the instability of sand dunes and its low nutrients. This species tolerates grazing animals and sand burial. It is considered as a good fodder for both domestic and wildlife animals. It has the potential to fix sand dunes. In addition, a preliminary observation indicated the presence of high contents of oil in the seeds. Despite the ecological importance of C. conglomeratus, little information is available about germination behaviour and seed composition. The present study assessed the dormancy, germination requirement, tolerance to salinity and drought during germination stage, the impact of dormancy regulation …

Environmental Catalysis By Nanostructured Chromium Oxides: Methanol Conversion To Dimethyl Ether As A Clean Fuel Alternative, Mariam Humaid Salem Al-Shamisi

Theses

Heterogeneous catalysts which are mainly based on metal particles and metal oxides have shown promising activity and selectivity in several environmental and industrial important reactions. Catalysis plays a key role in chemical and material manufacturing, fuel cells as well as other energy conversion and pollution control systems. Petroleum and fuel industry, in particular, rely largely on heterogeneous catalysis. Since catalysts play such a critical role in essential processes, the search for more effective and selective catalysts continues to be of great importance for both environmental and commercial considerations. The current study focuses on the catalytic conversion of methanol to other …

The Problem With Particularized Injury: The Disjuncture Between Broad-Based Environmental Harm And Standing Jurisprudence, Hope M. Babcock

Georgetown Law Faculty Publications and Other Works

Several recent events harmonically converged into the topic for this article. The first was a posting on Georgetown Law’s environmental law professors’ listserv by Professor John Bonine, which raised a number of questions about whether and how standing doctrine might be rethought in light of the Supreme Court’s opinion in Massachusetts v. EPA. That opinion relaxed the states’ standing burden because of the unique sovereign interests, finding that federalism bargaining earned states “special solicitude” when it came to meeting the Court’s standing requirements.

The second was a complaint filed by a consortium of regional environmental organizations, Chesapeake Bay Foundation, …

Widening The Evaluation Net, Brian Mac Namee, Mark Dunne

Conference papers

Intelligent Virtual Agent (IVA) systems are notoriously difficult to evaluate, particularly due to the subjectivity involved. From the various efforts to develop standard evaluation schemes for IVA systems the scheme proposed by Isbister & Doyle, which evaluates systems across five categories, seems particularly appropriate. To examine how these categories are being used, the evaluations presented in the proceedings of IVA '07 and IVA '08 are summarised and the extent to which the five categories in the Isbister & Doyle scheme are used is highlighted. Finally, to illustrate how the full scheme can be used, an evaluation of an IVA system …

Functionalized Heterofullerenes For Hydrogen Storage, Qiang Sun, Qian Wang, Puru Jena

Physics Publications

Using density functional theory, we show that Li decorated B doped heterofullerene (Li12C48B12) has the following desired properties of a hydrogen storagematerial. (1) The Li atoms remain isolated. (2) Through charge transfer to electron deficient C48B12 heterofullerene, the Li atoms become positively charged. (3) Each Li atom is able to bind up to three H2molecules, which remain in molecular form, and the binding energies of successive H2molecules are in the range of 0.135–0.172 eV/H2, suitable for ambient temperature storage. (4) The gravimetric density reaches the 9 wt % limit necessary for applications in the mobile industry.

Superhalogen Properties Of Cufn Clusters, Q. Wang, Q. Sun, P. Jena

Physics Publications

A first-principles calculation based on gradient corrected density functional theory reveals unusual properties of a Cu atom interacting with F. Up to six F atoms are bound to a single Cu atom with electron affinities steadily rising as successive F atoms are attached, reaching a peak value of 7.2 eV in CuF5. The large energy gaps between the highest occupied and lowest unoccupied molecular orbitals, both in neutral and anionic form, provide further evidence of their stability. These unusual properties brought about by involvement of inner shell 3d-electrons not only allow CuFn to belong to the class of superhalogens but …

Stabilizing A 22 Karat Nanogolden Cage, Q. Wang, Q. Sun, P. Jena

Physics Publications

Since the discovery of C60 fullerene, considerable efforts have been devoted to find other elements with similar hollow cage structures. However, search for hollow metallic cages with a diameter similar to that of C60 fullerene has been elusive. We describe a procedure for the rational design of metallic cages by suitably choosing their size, composition, and charge state. A 22 karat nanogolden cage with a diameter of about 8.5 Å and consisting of 12 Al and 20 Au atoms is found to be metastable, which can be stabilized by embedding a Mn4 cluster. In contrast to bulk Mn, which is …

Mg-Doped Gan Nanostructures: Energetics, Magnetism, And H2 Adsorption, Qian Wang, Qiang Sun, Puru Jena, Yoshiyuki Kawazoe

Physics Publications

Using density functional theory and generalized gradient approximation for exchange and correlation potential we show that Mg-doped GaN nanocages and nanotubes can be magnetic with Mg-contributed spins distributed over the neighboring N sites. Mg atoms show no tendency for clustering due to the positive charge residing on them; they can trap hydrogen in molecular form via the charge polarization mechanism. The binding energies of hydrogen lie in the range of 0.1–0.2 eV/H2, which are ideal for storage applications under ambient thermodynamic conditions.

Photoadsorption And Photodesorption For Gan, M. Foussekis, A. A. Baski, Michael A. Reshchikov

Physics Publications

The effect of an ambient environment on the surface photovoltage and photoluminescence observed for GaN is studied. In air ambient the upward band bending gradually increases under UVillumination and is explained by the photoinduced chemisorption of surface adsorbates. Specifically, the increase in negative surface charge is consistent with the transfer of electrons from surface states or bulk to oxygen species physisorbed at the GaNsurface. In contrast, the upward band bending gradually decreases in vacuum under UVillumination and can be explained by the photoinduced desorption of these species. The photoadsorption and photodesorption of negatively charged species cause the surface depletion region …

Highly Efficient (Cs8v) Superatom-Based Spin-Polarizer, Haiying He, Ravindra Pandey, J. Ulises Reveles, Shiv N. Khanna, Shashi P. Karna

Physics Publications

Quantum transport through molecules and the possibility to manipulate spin has generated tremendous excitement. Here, we demonstrate unusual spin transport through a molecule of twoCs8V magnetic superatoms. Calculations based on density functional theory and nonequilibrium Green’s function methods find a much higher current for the spin-down charge carriers relative to the spin-up carriers in the model Au–(Cs8V)–(Cs8V)–Au device system with almost 100% spin polarization, indicating a highly efficient spin polarizer. The new behavior is rooted in strong coupling of the localized magnetic core on V and the itinerant electrons of the Cs shell atoms leading to nearly full spin polarization.

Stable T2sin (T=Fe,Co,Ni,1≤N≤8) Cluster Motifs, R. Robles, S. N. Khanna

Physics Publications

First principles studies on the geometry, electronic structure, and magnetic properties of neutral and anionic Fe2Sin, Co2Sin, and Ni2Sin (1≤n≤8) clusters have been carried out within a gradient corrected density functional framework. It is shown that these clusters display a variety of magnetic species with varying magnetic moment and different magnetic coupling between the two transition metal atoms. While Fe2Sin clusters are mostly ferromagnetic with large moments, Ni2Sin clusters are mostly nonmagnetic. Our studies of the variation of the binding energy upon addition of successive Si atoms and the gap between the highest occupied molecular orbital and the lowest unoccupied …

2009 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.

Effect Of Hydrologic Restoration On The Habitat Of The Cape Sable Seaside Sparrow, 2008 – Final Report, Jay P. Sah, Michael S. Ross, James R. Snyder, Pablo L. Ruiz, Susana Stofella, Mike Kline, Broke Shamblin, Erin Hanan, Lawrence Lopez, T.J. Hilton

SERC Research Reports

This document summarizes the activities that were accomplished in 2008, the sixth year of the research project “Effect of hydrologic restoration on the habitat of the Cape Sable seaside sparrow”, a collaborative effort among the US Army Corps of Engineers, Everglades National Park, Florida International University, and the US Geological Survey (Florida Integrated Science Center). The major activities in 2008 included field work, data analysis, and presentations. Jay Sah presented the results of 6th year field work at the Cape Sable seaside sparrow (CSSS) Fire Meeting 2008, held on December 2-3 at the Krome Center, Homestead, Florida. In the same …

Rebuilding After Disaster: Going Green From The Ground Up, U.S. Department Of Energy

Publications (E)

If you’re a leader in a community that has met with disaster and must be rebuilt, this guide is for you. It’s intended to show how communities—big or small—can incorporate green principles and technologies like energy efficiency and renewable energy into their rebuilding plans. The information in this guide is based on the real-life experiences of two U.S. Department of Energy (DOE) teams. One team worked with city leaders in New Orleans, Louisiana, after hurricanes Katrina and Rita in 2005, and the other assisted community leaders in Greensburg, Kansas, after a devastating tornado in 2007. Although the two communities are …

The 2009 Unlv Campus Sustainability Survey Report, Mark J. Salvaggio

Reports (USI)

In an effort to understand environmental awareness, concerns, practices, and values at the University of Nevada, Las Vegas (UNLV), the Urban Sustainability Initiative (USI) conducted its first campus environmental sustainability survey during the months of March, April, and May 2009. This pilot study was developed to collect baseline data from students, faculty, and staff members at the UNLV campus to be used in a longitudinal study that assesses attitudes and preferences towards environmental sustainability issues. This research project is guided by one of the major goals of USI, which involves reaching out to the academic community to help find workable …

Equational Coalgebraic Logic, Alexander Kurz, Raul Leal

Engineering Faculty Articles and Research

Coalgebra develops a general theory of transition systems, parametric in a functor T; the functor T specifies the possible one-step behaviours of the system. A fundamental question in this area is how to obtain, for an arbitrary functor T, a logic for T-coalgebras. We compare two existing proposals, Moss’s coalgebraic logic and the logic of all predicate liftings, by providing one-step translations between them, extending the results in [21] by making systematic use of Stone duality. Our main contribution then is a novel coalgebraic logic, which can be seen as an equational axiomatization of Moss’s logic. The three logics are …

Etching Of Silicon In Fluoride Solutions, Kurt W. Kolasinski

Chemistry Faculty Publications

No abstract provided.

Stain Etching With Fe(Iii), V(V), And Ce(Iv) To Form Microporous Silicon, M E. Dudley, Kurt Kolasinski

Chemistry Faculty Publications

Stain etchants made from (HF+V(2)O(5)) or (HF+FeCl(3)center dot 6H(2)O+HCl or H(2)SO(4)) exhibited virtually no initiation time before the formation of porous silicon. Etching with Fe(III) solutions for extended periods resulted in a unique dual layer structure that can reach a thickness >10 mu m and exhibited not only red-orange but also green photoluminescence (PL). Etching with (CeF(4)+H(2)SO(4)) produced extremely uniform films. Visible PL was observed immediately after etching except for those films produced with (CeF(4)+H(2)SO(4)), which required several days of air exposure before bright and robust PL developed.

Using Decision Analytic Modelling To Simulate Pregnancy, Jeffrey Cannon

Theses : Honours

Decision analytic modelling enables decision makers to assess the cost-effectiveness associated with a proposed change in a cunent system without physically implementing the changes. This can be achieved by formulating a mathematical model that represents all the major events occuning in the system through fmmulas and algorithms, and estimating the likely outcomes along with their costs. This type of modelling has been identified by the State Health Research Advisory Council (SHRAC) of the Western Australian Depmiment of Health as an asset for the plmming of health care investments in the future. One such area in which the Western Australian Department …

Electronic To Vibrational Energy Transfer From Cl* (2P1/2) To Ch4 And Cd4, Brian R. Munson

Browse all Theses and Dissertations

Electronic-to-vibrational (E-V) energy transfer is a significant kinetic channel in the collisional quenching of spin-orbit excited chlorine atoms, Cl^* (²P_1/2, 882 cm^-1), by molecular collision partners. In the present study Cl^* atoms are prepared in the presence of CH₄ or CD₄, under pseudo first-order conditions, by photolysis of ICl at 532 nm with a pulsed Nd:YAG laser. Quenching of Cl^* by CH₄ or CD₄ results in E-V excitation of the ν4 asymmetric bending mode as observed by infrared (IR) fluorescence from the vibrationally excited products. Time-resolved …

Investigation And Quantification Of Codon Usage Bias Trends In Prokaryotes, Amanda L. Hanes

Browse all Theses and Dissertations

Organisms construct proteins out of individual amino acids using instructions encoded in the nucleotide sequence of a DNA molecule. The genetic code associates combinations of three nucleotides, called codons, with every amino acid. Most amino acids are associated with multiple synonymous codons, but although they result in the same amino acid and thus have no effect on the final protein, synonymous codons are not present in equal amounts in the genomes of most organisms. This phenomenon is known as codon usage bias, and the literature has shown that all organisms display a unique pattern of codon usage. Research also suggests …

Bench-Scale Conversion Of Carbon Dioxide To A Hydrocarbon Fuel, Melissa L. Kennedy

Browse all Theses and Dissertations

There is a growing concern about the effects of global warming that many believe is anthropogenically caused. As such, scientists are trying to uncover a viable alternative fuel source and establish a way to reduce atmospheric carbon dioxide levels. A potential solution that addresses both of these aspects would be to capture atmospheric carbon dioxide and convert it into a natural gas, in particular methane, which could be used as an energy source. A laboratory-scale experiment using 6 160 mL microcosms (3 with anaerobic wetland soil and 3 relatively soil free) and 2 7.2 L bioreactors was conducted to learn …