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The overarching theme of this thesis involves the investigation of the electronic structures of porphyrin and phthalocyanine derivatives and the predictable manipulation of their molecular orbital energy levels induced via changes in aromatic macrocyclic structure, peripheral substitution, or axial ligation. Using both experimental spectroscopic (UV-vis, circular dichroism, magnetic circular dichroism) and theoretical (density functional theory and time-dependent DFT) techniques, the electronic structures of these macrocyclic systems were studied to provide tunable platforms to best suit their specific applications. Intended outcomes for these compounds include their use as photosensitizers for the photodynamic therapy of cancer, chemical sensors, and molecular wires.

Designed to assist chemistry teachers in selecting appropriate software programs, this publication is the sixth in a series of six teacher's guides from Project SERAPHIM, a program sponsored by the National Science Foundation. This guide is keyed to the chapters of the text "Chemistry: The Study of Matter." Program suggestions are arranged in the same order as the chapters of the textbook and are classified by topic and by type of classroom use. Information on each program includes: (1) name; (2) disk number; (3) topics; (4) grade levels; and (5) a description. Guidance is also offered regarding methods by which each program can be used most effectively. Summary lists of recommended programs for Apple, IBM, and Commodore systems, as well as for other microcomputers, are provided. Specified in these lists are the SERAPHIM disk number, the hardware availability, the program's name(s), and the recommended chapters for use. (ML)

Designed to assist chemistry teachers in selecting appropriate software programs, this publication is the first in a series of six teacher's guides from Project SERAPHIM, a program sponsored by the National Science Foundation. This guide is keyed to the chapters of the text "Chemistry: Experimental Foundations." Program suggestions are arranged in the same order as the chapters of the textbook and are classified by topic and by type of classroom use. Information on each program includes: (1) name; (2) disk number; (3) topics; (4) grade levels; and (5) a description. Guidance is also offered regarding methods by which each program can be used most effectively. Summary lists of recommended programs for Apple, IBM, and Commodore systems, as well as for other microcomputers, are provided. Specified in these lists are the SERAPHIM disk number, the hardware availability, the program's name(s), and the recommended chapters for use. (ML)

Designed to assist chemistry teachers in selecting appropriate software programs, this publication is the fifth in a series of six teacher's guides from Project SERAPHIM, a program sponsored by the National Science Foundation. This guide is keyed to the chapters of the text "Chemistry: The Central Science." Program suggestions are arranged in the same order as the chapters of the textbook and are classified by topic and by type of classroom use. Information on each program includes: (1) name; (2) disk number; (3) topics; (4) grade levels; and (5) a description. Guidance is also offered regarding methods by which each program can be used most effectively. Summary lists of recommended programs for Apple, IBM, and Commodore systems, as well as for other microcomputers, are provided. Specified in these lists are the SERAPHIM disk number, the hardware availability, the program's name(s), and the recommended chapters for use. (ML)

Designed to assist chemistry teachers in selecting appropriate software programs, this publication is the third in a series of six teacher's guides from Project SERAPHIM, a program sponsored by the National Science Foundation. This guide is keyed to the chapters of the text "Modern Chemistry." Program suggestions are arranged in the same order as the chapters of the textbook and are classified by topic and by type of classroom use. Information on each program includes: (1) name; (2) disk number; (3) topics; (4) grade levels; and (5) a description. Guidance is also offered regarding methods by which each program can be used most effectively. Summary lists of recommended programs for Apple, IBM, and Commodore systems, as well as for other microcomputers, are provided. Specified in these lists are the SERAPHIM disk number, the hardware availability, the program's name(s), and the recommended chapters for use. (ML)

Designed to assist chemistry teachers in selecting appropriate software programs, this publication is the fourth in a series of six teacher's guides from Project SERAPHIM, a program sponsored by the National Science Foundation. This guide is keyed to the chapters of the text "Chemistry: A Modern Course." Program suggestions are arranged in the same order as the chapters of the textbook and are classified by topic and by type of classroom use. Information on each program includes: (1) name; (2) disk number; (3) topics; (4) grade levels; and (5) a description. Guidance is also offered regarding methods by which each program can be used most effectively. Summary lists of recommended programs for Apple, IBM, and Commodore systems, as well as for other microcomputers, are provided. Specified in these lists are the SERAPHIM disk number, the hardware availability, the program's name(s), and the recommended chapters for use. (ML)

This document contains information on the hole in the ozone layer. Topics discussed include properties of ozone, ozone in the atmosphere, chlorofluorocarbons, stratospheric ozone depletion, effects of ozone depletion on life, regulation of substances that deplete the ozone layer, alternatives to CFCs and Halons, and the future of the ozone layer. (WRM)

A guide to help students from other countries pursue graduate education in chemistry in the United States is presented. The process of gaining admission to U.S. universities is emphasized, and the nature of graduate education is briefly explained. It is noted that students majoring in chemistry are expected to have a sound background in analytical, inorganic, organic, and physical chemistry. A representative list of textbooks used in U.S. chemistry departments in recent years is included for each subfield of chemistry, and a few mathematics and physics texts are also listed. Attention is also directed to preparation for foreign students entering graduate schools in chemistry, financial aid, selection of a graduate school in chemistry, and application to graduate schools. Steps in the application process and the associated time frame are covered, including entrance examinations. Finally, the names and addresses of U.S. and Canadian institutions that offer Ph.D. degrees in chemistry are presented. (SW)

An analysis of the relations between critical micellar concentrations and temperature, or pressure, indicates that experimental data fit on U shaped curves. It is shown that, irrespective of alkyl chain length, counterion and polar head group of the ionic surfactant, the dependence of CMCs on intensive variables can be expressed according to [CMC (X)/CMC*(X)-1] = \1-X/X*/η where η is an exponent and X the intensive parameter into account. The above fit allows the prediction of the dependence of CMCs on intensive variables in a wide range of experimental conditions. In addition, accurate values for the entropy of micelle formation can be obtained.

Morinda pubescens is used for the treatment of diabetes, liver diseases, wound healing, cancer etc and this study was aimed to screen the chloroform extract of Morinda pubescens leaves for biologically active compounds and to evaluate the antioxidant and anticancer potential against HepG2 cell lines. The antioxidant activity of extract and its isolated compounds were carried out using 2, 2 diphenyl-1-picrylhydrazyl assay using L- ascorbic acid as a standard. The tetrazolium salt 3-[4, 5 dimethylthiazol-2yl]-2,5diphenyl trazolium bromide was used to determine the cell viability against HepG2 cells and Caspase-3 and -9 carried out to find the mechanism of the cytotoxicity. Octonyl glucopyranose, the isolated bioactive compound was subjected to RT-PCR study to confirm the apoptotic activity. The results revealed that the chloroform extract and three isolated compounds namely phytol, Octonyl glucopyranose and hexonyl glucopyranose exhibited significant antioxidant activities with IC50 values of 550, 758, 482 and 645μg/mL respectively. The Octonyl glucopyranose one of the isolated bioactive compounds decreased the cell viability in HepG2 cells dose-dependently and increased the caspase-3 and caspase-9 protein levels to 1.3 folds than the normal cells. Augmentation of p53 expression was observed in the Octonyl glucopyranose treated cells than the untreated cells. These findings might offer valuable insights into the mechanism of anti-cancer activity of Octonyl glucopyranose HepG2 cells.

Controlled release of Levofloxacin Hemihydrate drug through Methyl Methacrylate grafted Poly (vinyl alcohol) (PVA-g-MMA) hydrogel membranes have been investigated. These graft co-polymer hydrogel membranes of various formulations were prepared using conventional solution casting method by varying, monomer, cross-linker and drug content. An attempt has been made to characterize these hydrogel membranes by various instrumental techniques like, Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). The release patterns of the drug from the hydrogel membrane were carried out in pH 7.4 media and the samples were analysed spectrophotometrically at 294 nm wavelength on a UV Vis spectrophotometer. The mechanical properties of the hydrogel membranes were characterized by UTM. FTIR spectra of the membranes indicated complete esterification of the free carboxyl groups of Methyl Methacrylate. XRD studies indicated that the crystallinity of the membranes was mainly due to Methyl Methacrylate. The experimental results indicated that the hydrogel membrane could be tried for various biomedical applications

In the past three years, our research project sponsored by AFOSR has been focused on developing low bandgap semiconducting polymers as both the donor and acceptor materials for BHJ solar cells. Research effort were also devoted to establish structure-property relationship and develop approaches to optimize light harvest, charge separation and charge collection, thus the overall power conversion efficiency (PCE). We have made very important contributions to the field and developed a series of new semiconducting polymers for highly efficient ternary polymer solar cells. We also discovered cooperative plasmonic effect of dual precious metal nanoparticles in enhancing PCE of BHJ solar cells. Multiwall carbon nanowire were introduced to significantly enhance the charge collection. These results have had significant impact to the area. Several polymers developed in our lab are now widely investigated around world. Seven of the papers published are highly cited as indicated by SCI., The original document contains color images.

Cordia macleodii Hook (boraginaceae), a folklore medicinal plant, commonly known as "Shikari" in local language and found in Odisha and Madhya Pradesh. In this study, total phenolic content and concentration of flavonoids of two different extracts, from the ethanolic extract of Cordia macleodii (Boraginaceae) were determined using spectrophotometric methods. The total phenolic content ranged from 0.65±0.05 & 1.65±0.12 mg/g of dry weight of leaves & bark extract, expressed as gallic acid equivalents. The total flavonoids concentrations varied from 0.985±0.09 & 1.89±0.11 mg/g in bark & leaves extract, expressed as quercetin equivalents. Ethanolic extract of bark & leaves of Cordia macleodii showed the highest phenolic and flavonoids concentration repectively. The Cordia macleodii can be regarded as promising candidates for health management because of natural plant sources of phenolic and flavonoids with high value.

The development of injectable microspheres for controlled drug delivery to the desired site is a major challenge. We demonstrated the possibility of entrapping an anticancer drug, Imatinib mesylate, in collagen coated biodegradable poly (lactic acid) microspheres with a mean diameter of 10-20 µm. The collagen coating on polymeric matrix surfaces through various surface modification techniques was the current scenario to improve bio-integration of the polymers with the in-vivo system. Here protein adsorption principle is used and various characterization techniques like FTIR, DSC and SEM analysis are used to confirm collagen coating. The reduction in burst release of the Imatinib from the PLA microspheres further confirms its presence and role in controlled release. This collagen coated PLA microspheres may have potential for the targeted delivery of Imatinib mesylate to treat gastrointestinal stromal tumors, chronic myeloid leukemia cancer.

A fundamental understanding of the surface chemistry of chemical warfare agents is needed to fully predict the interaction of these toxic molecules with militarily relevant materials, catalysts, and environmental surfaces. For example, rules for predicting the surface chemistry of agents can be applied to the creation of next generation decontaminants, reactive coatings, and protective materials for the warfighter. Here, we describe a multifunctional ultra-high vacuum instrument for conducting comprehensive studies of the adsorption, desorption, and surface chemistry of chemical warfare agents on model and militarily relevant surfaces. The system applies reflection-absorption infrared spectroscopy, x-ray photoelectron spectroscopy, and mass spectrometry to study adsorption and surface reactions of chemical warfare agents. Several novel components have been developed to address the unique safety and sample exposure challenges that accompany the research of these toxic, often very low vapor pressure, compounds. While results of vacuum-based surface science techniques may not necessarily translate directly to environmental processes, learning about the fundamental chemistry will begin to inform scientists about the critical aspects that impact real-world applications., Published in the Journal of Review of Scientific Instruments, v85 n1 p1-9, 2014. The original document contains color images.

Constrained by large ohmic and radiation losses, plasmonic nanolasers operated at visible regime are usually achieved either with a high threshold (100-10,000 MW/sq cm) or at cryogenic temperatures (4-120 K). Particularly, the bending-back effect of surface plasmon (SP) dispersion at high energy makes the SP lasing below 450nm more challenging. Here we demonstrate the first strong room temperature ultraviolet (370 nm) SP polariton laser with an extremely low threshold (3.5MW/sq cm). We find that a closed-contact planar semiconductor-insulator-metal interface greatly lessens the scattering loss, and more importantly, efficiently promotes the exciton-SP energy transfer thus furnishes adequate optical gain to compensate the loss. An excitation polarization-dependent lasing action is observed and interpreted with a microscopic energy-transfer process from excitons to SPs. Our work advances the fundamental understanding of hybrid plasmonic waveguide laser and provides a solution of realizing room temperature UV nanolasers for biological applications and information technologies., Published in Nature Communications, 5:4953, 23 Sep 2014.

Catalyzed reactions are important for synthesizing new materials, for energy production and conversion, and for electrochemical, photochemical, and solar cells and devices. The objective of the project was to develop better orbital-dependent density functionals and improved algorithms for applications of computational chemistry to catalysis. The technical approach was to propose new functional forms for the density functional and new algorithms for applying them and to test and validate those functionals and algorithms by applications to databases of experimental and accurate theoretical data and to important practical problems in current catalytic research. At a fundamental level we continued to explore the questions of what functional dependences must be present in the exchange-correlation energy for density functional theory to have improved predictive ability for catalysis involving transition metals. The rest was that we developed improved methods for modeling catalysis, for improved catalytic ligand design, and for understanding and predicting selectivity and specificity in catalytic reactions., The original document contains color images.

In this study, the magnetic and magneto-optic properties of -conjugated polymers were investigated. This research was initiated by the observation of extremely strong Faraday rotation in films of pristine highly regioregular poly(3-alkylthiophene)s and subsequently a ferromagnetic hysteretic behavior at low temperature ( 20K) in these polymers. Concomitantly nanoscopic doughnut structures (diameter 12 nm) were observed in such thin films spin coated from a poor solvent (toluene). Interestingly all such properties and structures were absent from regiorandom poly(3-alkylthiophene)s. Over the course of the project, we developed an extended portfolio of polythiophenes, achiral as well as chiral, which have been thoroughly characterized in their chemical properties. Faraday measurements on these polymers, in solution and thin films, have clearly shown the great potential of these polymers as materials for magneto-optical applications. The results of this project have also opened a new way to organic magnetism of environmental stable polymers, while on a more theoretical way the study of persistent currents in organic cyclic structures has been initiated., The original document contains color images.

This research concentrated on the growth and characterization of metal oxide ALD films on sp2-graphitic carbon substrates. Metal oxide ALD films on sp2-graphitic carbon were also evaluated for their ability to serve as electrodes for Li ion batteries and for pseudocapacitance supercapacitors. The research explored the ALD nucleation procedure based on NO2 and TMA. Al2O3 ALD films resulting from the nucleation procedure were analyzed using electrochemical methods with cyclic voltammetry and electrochemical impedance spectroscopy (EIS). Other metal oxide ALD films such as TiO2 and ZnO were used for electrodes for Li ion batteries and pseudocapacitance supercapacitors., The original document contains color images.

We demonstrated the design, synthesis, structural characterization, and study of photophysical properties of ultrafast photoresponsive starburst and dendritic C60/C70-light harvesting antenna-based organic nanostructures for broadband nonlinear optical (NLO) nanomaterial applications. These organic NLO nanostructures exhibit both ultrafast photoresponse and a large cross-section of two-photon absorption (2PA) throughout a wide NIR spectrum may make them also suitable for use as nonlinear biophotonic materials. With hybrid C60-(antenna)x analogous as branched triad and tetrad starburst nanostructures, 2PA characteristics at multiple NIR wavelengths provided support for their suitability in uses as broadband NLO nanomaterials at 600 1100 nm that includes the 2PA ability of two antenna, DPAF (700 850 nm) and CPAF (850 1100 nm), and the fullerene cage at shorter wavelengths (600 700 nm) to build broadband NLO characteristics. A new molecular encapsulation of C70-(antenna)1or2 conjugates by helical st-PMMA was also perform., The original document contains color images.

While living systems have developed highly efficient ways to convert chemical energy (e.g., ATP hydrolysis) to mechanical motion (e.g., movement of muscle), it remains a challenge to build muscle-like biomimetic systems to generate mechanical force directly from chemical reactions. Here we show that a continuous flow of reactant solution leads to by far the largest volume change to date in autonomous active gels driven by the Belousov Zhabotinsky reaction. These results demonstrate that microfluidics offers a useful and facile experimental approach to optimize the conditions (e.g., fabrication methods, counterions, flow rates, concentrations of reagents) for chemomechanical transduction in active materials. This work thus provides much needed insights and methods for the development of chemomechanically active systems based on combining soft materials and microfluidic systems., Pub. in Journal of the American Chemical Society, v136, p7341-7347, 2014.

We study the dynamical behavior of one-dimensional arrays of B100 mm diameter aqueous droplets containing the oscillatory Belousov Zhabotinsky (BZ) reaction, separated by narrow gaps of a fluorinated oil. In this closed system, the malonic acid concentration decreases as the reaction proceeds. Starting with a low initial malonic acid concentration, we observe a series of attractors as a function of time in the following order: anti-phase attractors; in-phase attractors, which evolve into traveling waves; and mixed modes that contain either regions of in-phase droplets separated by anti-phase oscillators, or in-phase oscillators combined with non-oscillatory droplets. Most of the observations are consistent with numerical chemical models of the BZ reaction in which components that participate in the excitatory (bromine dioxide and bromous acid) and inhibitory (bromine) pathways diffuse between the droplets. The models are used to quantitatively assess the inter-drop coupling strength as a function of drop separation, drop size and malonic acid concentration. To experimentally establish the mechanism of excitatory coupling between the BZ droplets, we verify the transport through the fluorinated oil of chlorine dioxide and several weak acids, including malonic acid., Published in Physical Chemistry Chemical Physics v16 p10965-10978, 2014.

Two-photon absorption (TPA) is a phenomenon of great interest for various optical limiting applications. The enhancement of molecular TPA cross-sections by placement of TPA chromophores within the plasmonic field of resonant and nonresonant plasmonic gold nanoparticles was explored. Polyelectrolyte layer-by-layer wrapping was employed to provide spacer layers between the chromophores and the gold surface. For on-resonant cases, TPA cross-sections could be enhanced by a factor of 40 for chromophores closest to the gold surface. The distance dependence of the TPA cross-section enhancement followed the calculated electric field. In contrast, for off-resonant gold nanoparticles, the calculated electric field dependence decreased then increased as a function of distance from the gold surface, in accord with experiment. Finally, TPA chromophores were covalently attached to the wrapping layers to put the chromophores even closer to the gold surface; but the observed distance dependence was flat, suggesting that chromophore orientation may have been compromised by covalent attachment., The original document contains color images.

Two nitroiminotetrazole compounds, 1,2-bis(4,5-dihydo-5-nitroimino-1H-tetrazol-1-yl)ethane and bis(hydrazinium) ethylene bis(5-nitroiminotetrazolate) appeared to have properties that suggested further study to determine their value as replacements for RDX. They were synthesized in our laboratory (2.5 - 3.0 grams) and shipped as aqueous solutions to NSWC, Indian Head for safety tests (impact sensitivity, friction sensitivity, and ESD). Results indicate that the two candidates, while superior to RDX in enthalpy of formation and detonation properties, with respect to the safety tests, they exhibit roughly RDX sensitivities. Thus, it is unlikely that they would be competitive as replacements for RDX., The original document contains color images.

This research program is focused on development of organometallic chromophore systems for application in temporal and frequency agile non-linear absorption materials. The program is based on prior investigations carried out in our labs in which a new class of organometallic materials have been developed that display non-linear absorption via a dual-mode mechanism involving two-photon absorption (2PA) and excited state absorption (ESA). The work has the broad objective of developing new organometallic chromophores and materials that display very effective non-linear response to laser pulses ranging from picoseconds to nanoseconds in the visible and near-infrared spectral regimes. The project is carried out primarily at the University of Florida, in close coordination with the Agile Limiting group at the Air Force Research Laboratory/Materials and Manufacturing Directorate (AFRL/MLPJ) in order to complement their ongoing efforts which are related development of materials for non-linear optical application. Materials developed in the proposed program that exhibit promising non-linear absorption properties will be transitioned to the AFRL/MLPJ group for more extensive testing in specific optical limiting formats., The original document contains color images.

The objectives of this grant were to (a) examine the solution crystallization of RDX, HMX and CL-20 from a variety of solvents, with detailed analysis of their phase, size, and morphological properties; (b) to prepare and fully characterize a library of gold-thiol and siloxane monolayers that can serve as crystal nucleation templates and (c) to assess the growth of RDX, HMX and CL-20 on these templates., The original document contains color images.

The ultimate goal of this project is to develop a viable C-coating process of the current collector in order to improve the overall power performance of the electrode of Li-ion batteries. During this third-year period, the performance of different thickness of carbon coating on Al foil is compared. The result shows that only the samples with sufficient thickness to form conductive channel on the surface would give a positive effect on the performance. Scale up of this coating process is further developed to make 1.5 m long C-coated tape by a contentious process followed with a special batch thermal process called roll-calcination. The same positive effects seen on small samples have been reproduced., The original document contains color images. Sponsored in part by AOARD (rept. #AOARD-124092).

Poly (lactic-co-glycolic acid) nanoparticles loaded with Aripiprazole has been developed as a new therapeutic strategy to achieve its controlled release profile suitable for parenteral administration. Nanospheres composed of different lactic/glycolic acid ratios and drug compositions were synthesized and loaded with Aripiprazole by emulsion/solvent evaporation method and subsequently characterized by particle-size distribution, scanning electron microscopy, encapsulation efficiency and in–vitro drug release studies. Specific drug-polymer interactions are engineered by optimizing the lactide to glycolide ratio (L:G ratio) and including specific polymer hydrophobicity.

Corrosion inhibition of aluminium in 1N NaOH by leaves extract of Senna auriculata (SL) was studied using chemical and electrochemical techniques at 30-60°C. It was found that the leaves of Senna auriculata inhibited the base induced corrosion of aluminium.The inhibition efficiency increases with increase in concentration of SL extract and reached the maximum of 76.2% but decrease with rise in temperature. The adsorption of SL on metal surface obeyed Langmuir adsorption isotherm. Polarization measurements showed that SL extract acted as mixed type inhibitor. The surface morphology of aluminium, in the absence and presence of SL extract in 1N NaOH solution, was studied using scanning electron microscopy. Results obtained from chemical and electrochemical techniques were in good agreement. Thermodynamic parameters such as activation energy and free energy of adsorption were calculated and given in kJ/mol.