Other Chemistry Commons^™

Three-Dimensional Periodic Graphene Nanostructures, Peter M. Wilson, Gilbert N. Mbah, Thomas G. Smith, Daniel Schmidt, Rebecca Y. Lai, Tino Hofmann, Alexander Sinitskii

Department of Chemistry: Faculty Publications

Graphene is a basic building block for many known and emerging carbon-based materials whose properties largely depend on the way how graphene is structured at the nanoscale. Synthesis of novel threedimensional (3D) nanostructures of graphene would be an important advance for fundamental research and various applications. In this paper, we discuss the possibility of fabricating complex 3D graphene nanostructures by growing graphene on pre-synthesized nanostructured metal templates by chemical vapor deposition (CVD) and then etching away the metal. In the proof-of-concept experiments, we study this idea using two types of metal nanostructures, inverse opals and slanted nanopillar arrays grown by …

Bulk Properties Of Solution-Synthesized Chevron-Like Graphene Nanoribbons, Timothy H. Vo, Mikhail Shekhirev, Alexey Lipatov, Rafal A. Korlacki, Alexander Sinitskii

Department of Chemistry: Faculty Publications

Graphene nanoribbons (GNRs) have received a great deal of attention due to their promise for electronic and optoelectronic applications. Several recent studies have focused on the synthesis of GNRs by the bottom-up approaches that could yield very narrow GNRs with atomically precise edges. One type of GNRs that has received a considerable attention is the chevron-like GNR with a very distinct periodic structure. Surface-assisted and solution-based synthetic approaches for the chevron-like GNRs have been developed, but their electronic properties have not been reported yet. In this work, we synthesized chevron-like GNRs in bulk by a solution-based method, characterized them by …

Highly Selective Gas Sensor Arrays Based On Thermally Reduced Graphene Oxide, Alexey Lipatov, Alexey Varezhnikov, Peter Wilson, Victor Sysoev, Andrei Kolmakov, Alexander Sinitskii

Department of Chemistry: Faculty Publications

The electrical properties of reduced graphene oxide (rGO) have been previously shown to be very sensitive to surface adsorbates, thus making rGO a very promising platform for highly sensitive gas sensors. However, poor selectivity of rGO-based gas sensors remains a major problem for their practical use. In this paper, we address the selectivity problem by employing an array of rGO-based integrated sensors instead of focusing on the performance of a single sensing element. Each rGO-based device in such an array has a unique sensor response due to the irregular structure of rGO films at different levels of organization, ranging from …

Structure And Function Of Preq1 Riboswitches, Catherine D. Eichhorn, Mijeong Kang, Juli Feigon

Department of Chemistry: Faculty Publications

PreQ₁ riboswitches help regulate the biosynthesis and transport of PreQ₁ (7-aminomethyl-7- deazaguanine), a precursor of the hypermodified guanine nucleotide queuosine (Q), in a number of Firmicutes, Proteobacteria, and Fusobacteria. Queuosine is almost universally found at the wobble position of the anticodon in asparaginyl, tyrosyl, histidyl and aspartyl tRNAs, where it contributes to translational fidelity. Two classes of PreQ₁ riboswitches have been identified (PreQ₁-I and PreQ₁-II), and structures of examples from both classes have been determined. Both classes form H-type pseudoknots upon PreQ₁ binding, each of which has distinct unusual features and modes …

Metallurgical And Corrosion Assessment Of Submerged Tanker S.S. Montebello, Dana Medlin, James D. Carr, Donald L. Johnson, David L. Conlin

Department of Chemistry: Faculty Publications

The Union Oil Tanker S.S. Montebello was torpedoed and sunk six miles (9.7 km) off the coast of Cambria, California by a Japanese submarine on December 23, 1941, two weeks after the attack on Pearl Harbor. With close proximity to the National Monterey Bay Marine Sanctuary, concern about possible crude oil contamination led to the most recent expedition to the site in October 2011. Assessment of the shell plate found that the average corrosion rate was very low and the structure will remain stable for many decades.

Advances In Chemical And Structural Characterization Of Concretion With Implications For Modeling Marine Corrosion, Donald L. Johnson, Robert J. Deangelis, Dana J. Medlin, James D. Carr, David L. Conlin

Department of Chemistry: Faculty Publications

The Weinsnumber model and concretion equivalent corrosion rate methodology were developed as potential minimum-impact, cost-effective techniques to determine corrosion damage on submerged steel structures. To apply the full potential of these technologies, a detailed chemical and structural characterization of the concretion (hard biofouling) that transforms into iron bearing minerals is required. The fractions of existing compounds and the quantitative chemistries are difficult to determine from x-ray diffraction. Environmental scanning electron microscopy was used to present chemical compositions by means of energy-dispersive spectroscopy (EDS). EDS demonstrates the chemical data in mapping format or in point or selected area chemistries. Selectedarea EDS …

Analogues Of (-)-Picropodophyllin, Synthesis And Uses Thereof, David B. Berkowitz, Sylvain Broussy

Department of Chemistry: Faculty Publications

Analogs of (-)-Picropodophyllin, synthesis thereof, and uses in pharmaceuticals as inhibitors of IGF1RK.

Electron And Ion Spectroscopy Of Metal Hydrocarbon Complexes, Sudesh Kumari

Theses and Dissertations--Chemistry

Metal-hydrocarbon complexes were prepared in a laser-vaporization molecular beam source and studied by single-photon zero electron kinetic energy (ZEKE) and mass-analyzed threshold ionization (MATI) spectroscopy. The ionization energies and vibrational frequencies of the metal complexes were measured from the ZEKE and MATI spectra. Metal-ligand bonding and low-lying electronic states of the neutral and ionized complexes were analyzed by combining the spectroscopic measurements with quantum chemical calculations and spectral simulations.

In this dissertation, the metal complexes of mesitylene, aniline, cyclooctatetraene, benzene, ethene, and propene were studied. For each complex, different effects from metal coordination have been identified. Although metal-bis(mesitylene) sandwich complexes …

Structure Vs. Properties Using Chemical Graph Theory, Tabitha N. Williford

College of Graduate Studies: Theses & Dissertations

Chemical graph theory began as a way for mathematicians to bring together the areas of the Physical Sciences and Mathematics. Through its use, mathematicians are able to model chemical systems, predict their properties as well as structure-property relationships. In this dissertation, we consider two questions involving chemical graph theory and its applications. We first look at tree-like polyphenyl systems, which form an important family of compounds in Chemistry, particularly in Material Science. The importance can be seen in LEDs, transmitters, and electronics. In recent years, many extremal results regarding such systems under specific constraints have been reported. More specifically are …

Investigations Into The Fluorescent Covalent Labeling Of Biomolecules Utilizing Rhodamine Dyes, Electrophilic Leaving Groups And Mrna Display., Susan D. Selaya

Theses and Dissertations

The discovery of a method by which proteins of interest can selectively be labeled with a probe of choice intracellularly is a longstanding goal in chemical biology research. Conventional labeling techniques have utilized large domain tags but despite the development of small labeling molecules there have been no short peptide sequences known to covalently label a small molecule without the aid of an enzymatic process or metal chelation. We aimed to find a sequence of nucleophilic peptides that reacted covalently and specifically with electrophilic small labeling molecules using mRNA display. Our goal was to show that an electrophilic small labeling …

Light Mediated Drug Delivery Using Photocaged Molecules And Photoswitchable Peptides, Deboleena Mitra

Theses and Dissertations

There are many different types of targeted therapy for cancer treatment. The method of light mediated targeted therapy that we have developed uses photocaged molecules and photoswitchable peptides.

In photocaging, a biologically active molecule is made inactive by the attachment of a photocleavable blocking group. On exposure to UV radiation the photocleavable entity is removed and the biologically active molecule is released. Using this concept we have designed a prodrug that consists of a cell impermeable hydrophilic molecule attached to a photocaged doxorubicin. Upon irradiation with UV light the photosensitive group is removed and cytotoxic doxorubicin is released at the …