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Full-Text Articles in Physical Sciences and Mathematics

Synthesis And Characterization Of Highly Porous Borazine-Linked Polymers Via Dehydrogenation/Dehydrocoupling Of Borane-Amine Adducts And Their Applications To Gas Storage, Karl Jackson Dec 2011

Synthesis And Characterization Of Highly Porous Borazine-Linked Polymers Via Dehydrogenation/Dehydrocoupling Of Borane-Amine Adducts And Their Applications To Gas Storage, Karl Jackson

Theses and Dissertations

A new class of porous polymers has been designed and successfully synthesized by thermal dehydrogenation of several polytopic arylamine-borane adducts and has been designated Borazine-Linked Polymers (BLPs). The polymers reported are constructed of linear, triangular, and tetrahedral amine building units to form 2D and 3D frameworks. The boron sites of the pores are aligned with hydrogen atoms contrasted with the recently reported halogenated BLPs which consist of pore channels aligned with bromine or chlorine atoms. One of the reported BLPs, BLP-2(H), was proven to be crystalline by PXRD, matching the experimental pattern to theoretical patterns calculated from modeled structures. BLPs …


Designed Synthesis Of Halogenated Borazine-Linked Polymers And Their Applications In Gas Storage And Separation, Thomas Reich Dec 2011

Designed Synthesis Of Halogenated Borazine-Linked Polymers And Their Applications In Gas Storage And Separation, Thomas Reich

Theses and Dissertations

The synthesis of highly porous organic polymers with predefined porosity has attracted considerable attention due to their potential in a wide range of applications. Of particular interest in porous organic polymers is their potential use in automotive applications as well as separation processes whereby advancements could result in a reduction in carbon dioxide emissions and the production of natural gas in a more economically friendly manner. Along these pursuits, seven borazine-linked polymers (BLPs) have been synthesized through the introduction of p-phenylenediamine, 1,3,5-tris-(4-aminophenyl)benzene, benzidine, or tetra-(4-aminophenyl)methane with boron tribromide or boron trichloride followed by the thermolysis reaction of the resulting in …


The Effect Of Oxidation And Support On Tio2(110)-Supported Pdn (N=1-7) Clusters, S. Vincent Ong Nov 2011

The Effect Of Oxidation And Support On Tio2(110)-Supported Pdn (N=1-7) Clusters, S. Vincent Ong

Theses and Dissertations

First principles theoretical studies based on a gradient-corrected density functional approach have been carried out on the atomic and electronic properties and oxidation of Pdn (n=1-7) clusters supported on the TiO2(110) surface. The studies are aimed to address some of the fundamental issues related to the properties of supported Pdn clusters used as catalysts in oxidation reactions. Of those issues are the following: What are the atomic structures of Pdn clusters on the TiO2 surface? Upon oxidation, do O atoms from a dissociated O2 molecule spill over onto the underlying TiO2 sup- port? How strongly does spillover oxygen bind? What …


Design Of Control Release Drug Delivery System (Dds) For Imaging And Therapeutic Applications, Sweta Naik Sep 2011

Design Of Control Release Drug Delivery System (Dds) For Imaging And Therapeutic Applications, Sweta Naik

Theses and Dissertations

The main challenge in disease treatment is no more the discovery of new therapeutic drugs, but to provide targeted delivery of therapeutic drugs to specific sites without incurring systemic toxicity effects. An efficient way of reducing the toxicity is by encapsulating the drug with a biodegradable matrix that can provide controlled release of the drug along with local heating of the drug. Local heating can be obtained by incorporating magnetic iron oxide particles that heat upon exposure to AC electromagnetic fields. The magnetic iron oxide nanoparticles are also gaining much attention as MRI contrast agents. Thus it would be of …


Wetting Transitions At Nanostructured Surfaces, Yazdi Jamileh Seyed Sep 2011

Wetting Transitions At Nanostructured Surfaces, Yazdi Jamileh Seyed

Theses and Dissertations

Shape of a droplet atop a surface heterogeneity at a nanoscale. Small aqueous droplets on homogeneous surfaces, surrounded by a reservoir of vapor are inherently unstable. In contact with supersaturated vapor, the drops will keep growing until they coalesce and form a contiguous aqueous phase. Alternatively, if vapor pressure is below that of the droplets, the droplets gradually evaporate. Departing from this common picture, when nanoscale droplets sit above hydrophilic patches on a heterogeneous surface, at certain conditions they can maintain a stable volume, determined by the pertinent contact angle and the size of the patches. Only the region under …


Synthesis Of Cyclen Based Receptors And Their Use In Separations Biotechnology., Vivek Kaushik Aug 2011

Synthesis Of Cyclen Based Receptors And Their Use In Separations Biotechnology., Vivek Kaushik

Theses and Dissertations

A number of purification techniques such as adsorption, centrifugation, chromatography, extraction, distillation, filtration, precipitation etc. to name a few, are commonly used for the purification. However, due to a constant need of purification of even more complex crude mixtures, be it reaction mixtures, various proteins and DNA from cell extracts or medicinal compounds and fragrances from plant extracts, scientists needed to consistently develop new and improved techniques of purification. One such great advancement in the field of chromatography was the development of affinity chromatography. It revolutionized the field of bioseparations technology, and the dream of single stage purification of complex …


Growth Mechanisms Of Complex Organics In The Gas Phase And On Metal Nanoparticles Generated By A Laser Vaporization Process, Abdel Rahman Soliman May 2011

Growth Mechanisms Of Complex Organics In The Gas Phase And On Metal Nanoparticles Generated By A Laser Vaporization Process, Abdel Rahman Soliman

Theses and Dissertations

In this dissertation, the ion mobility mass spectrometry technique is used to study the possible mechanisms of formation of polyaromatic hydrocarbons (PAHs) and polyaromatic nitrogen-containing hydrocarbons (PANHs) via the ion-molecule reactions of acetylene neutrals with different aromatic cations, in order to infer the possible mechanisms of formation of PAHs and PANHs in different environments such as interstellar media under different ionizing conditions. Furthermore, this technique is used to probe structures, address the thermochemistry, and measure the kinetics of the product ions originated from these reactions. Reactions of benzene radical cations with acetylene produce styrene and naphthalene-type cations at high temperatures. …


Development Of Free-Label Sensing In Plastic Microfluidic Platforms Using Pulsed Streaming Potentials (Psp), Vera Fernando Luna May 2011

Development Of Free-Label Sensing In Plastic Microfluidic Platforms Using Pulsed Streaming Potentials (Psp), Vera Fernando Luna

Theses and Dissertations

This work deals with the development of a new label-free detection technique called Pulsed Streaming Potential (PSP). Its novelty relies on the adaptation of a classical electrokinetic phenomenon (streaming potential) into a tool which can evaluate molecular interplay in label-free fashion. Implementation of PSP to microfluidic platforms allowed the label-free sensing of binding events to plastic (modified and unmodified) surfaces. It was demonstrated the use of real time PSP in plastic microfluidic platforms for determination of kinetic parameters of the interaction of proteins and plastic surfaces. Moreover, initial change of PSP after adsorption of proteins showed to be proportional to …


Drug Design, Biological Activity, And Metabolic Consequences Of Cytotoxic Platinum Compounds: Utilizing Fluorescent Tagging To Understand Drug Action And Metabolism, Brad Benedetti Apr 2011

Drug Design, Biological Activity, And Metabolic Consequences Of Cytotoxic Platinum Compounds: Utilizing Fluorescent Tagging To Understand Drug Action And Metabolism, Brad Benedetti

Theses and Dissertations

Platinum drugs are among the most commonly used chemotherapeutics for the treatment of testicular, head and neck, ovarian, small cell lung, and colorectal carcinomas. Although the current set of platinum chemotherapeutics has proven somewhat successful, the overall success of platinum based drugs is limited due to acquired drug resistance and a limited range of tumor types that are treatable with the current regime. The development of novel cytotoxic platinum based compounds, both trans- and polynuclear, provides for the promising treatment of clinical platinum drug resistant tumors. While the cytotoxic activity of platinum drugs provides for a hopeful outlook, the ultimate …


The Synthesis, Characterization, And Upconverting Properties Of Erbium Doped; Ytterbium, Erbium Co-Doped Yttrium Oxysulfide Phosphors Under 808, 980, And 1560 Nm Excitation, James Wilkins Jan 2011

The Synthesis, Characterization, And Upconverting Properties Of Erbium Doped; Ytterbium, Erbium Co-Doped Yttrium Oxysulfide Phosphors Under 808, 980, And 1560 Nm Excitation, James Wilkins

Theses and Dissertations

Bulk yttrium oxysulfide phosphors were prepared using the polysulfide flux method. The morphology and structure was characterized using transmission electron microscopy and x-ray powdered diffraction. Visible emissions occurring near 530 and 550 nm and 660 - 670 nm consistent with the 2H11/2, 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions, respectively, were observed under 808, 980, and 1560 nm excitation. The upconverting mechanisms excited at 808, 980, and 1560 nm have been investigated in detail. The power dependent behavior of the upconverted emission intensities for singly doped erbium phosphors excited at 808 and 980 nm indicated a two-photon excitation process. …