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Full-Text Articles in Physical Sciences and Mathematics
A Study Of The Effects Of Titanium Dioxide Nanoparticles On The Fluorescent Intensity Of Fluorescent Compounds In The Presence Of Known Quenchers., Vivian Dzigbodi Koka
A Study Of The Effects Of Titanium Dioxide Nanoparticles On The Fluorescent Intensity Of Fluorescent Compounds In The Presence Of Known Quenchers., Vivian Dzigbodi Koka
Electronic Theses and Dissertations
Titanium Dioxide is a naturally occurring oxide of titanium. It has a wide range of uses in commercial products for providing whiteness and opacity. It has photocatalytic properties and can also be used to produce electricity in its nanoparticles form. This research is focused on investigating the effect of titanium dioxide nanoparticles in analysis of compounds using luminescence-based techniques. Quenching, which is one of the basic problems of fluorescent measurements, was studied in the presence of molecular oxygen and methyl iodide. The rutile phase of titanium dioxide nanoparticles was synthesized by the acid hydrolysis of titanium isobutoxide at low temperatures …
Nanoparticles For Mercury Abatement, Sunil Krishna Thanikanti
Nanoparticles For Mercury Abatement, Sunil Krishna Thanikanti
All Capstone Projects
Mercury is considered to be a global contaminant. It does not break down in the environment and can build up in living organisms. Mercury can be carried long distances on wind currents, staying in the atmosphere for long periods of time, when in its vapor form. High mercury exposure results in permanent nervous system and kidney damage. Mercury exists in three different chemical forms: elemental, inorganic, and organic. The routes of exposure can be inhalation, ingestion, or skin contact. Vapor from liquid elemental mercury and methyl mercury are more easily absorbed than inorganic mercury salts and can, therefore, cause more …
Positional Control Over Nanoparticle Deposition Into Nanoholes, Moshood K. Morakinyo, Shankar B. Rananavare
Positional Control Over Nanoparticle Deposition Into Nanoholes, Moshood K. Morakinyo, Shankar B. Rananavare
Chemistry Faculty Publications and Presentations
Controlled deposition of metal nanoparticles (NPs) into lithographic patterned nanoholes has been a major challenge. Electrostatic attraction was employed in directing gold NPs of precise size into e-beam lithographically patterned holes. Citrate stabilized gold NPs with a net negative surface charge were deposited on a positively charged well-bottom surface generated by adsorption of long-chain amino-terminated organosilane N-(2-aminoethyl)-11-aminoundecyltrimethoxy- silane (AATMS). Scanning electron microscopy (SEM) results indicate that deposition of NPs into patterned holes is a function of deposition time and NPs concentration. Other factors affecting NP fill fraction are thickness of silane and resist layer and spacing between the nanoholes.
Encapsulated Antibiotic Nanoparticles For Cranial Transplantation, Adusumilli Naga Anusha
Encapsulated Antibiotic Nanoparticles For Cranial Transplantation, Adusumilli Naga Anusha
All Capstone Projects
The purpose of this research is to develop a unique nanoparticulate system that is capable of delivering antibiotics in a locally applied and extended-release manner for patients receiving cranial replacement implants and bone grafting. This study involves three major components: first, encapsulate both hydrophobic antibiotics (chloramphenicol and rifampicine) and hydrophilic antibiotics (vancomycine and acyclovir) into nanoparticles. Second, incorporate antibiotic nanoparticles in a polymeric coating material (nitrocellulose plus 7.0% (w/v) polyvinylpyrrolidone) with a volatile carrier solvent (ethyl acetate or ethanol). Third, directly apply the resulting product from component 1 and 2 to polymethyl methacrylate (PMMA) cranial implants and hydroxylapatite (HA) bone …
Nanoencapsulated Drug-Carrying System For Photodynamic Antimicrobial Chemotherapy (Pact), Gopala Krishna Murthy Kalapala
Nanoencapsulated Drug-Carrying System For Photodynamic Antimicrobial Chemotherapy (Pact), Gopala Krishna Murthy Kalapala
All Capstone Projects
The purpose of this study is to develop nanoparticulate drug-carrying systems that are capable of directly delivering photodynamic antimicrobial agents to treat patients with chronic wounds. Chronic wounds are considered as a pandemic health problem. Approximately 1% to 2% of the population in developing countries has experienced a chronic wound during their lifetime. In the United State States, according to the American Academy of Dermatology, the expense of treating chronic wounds constitutes over half of the total cost for all skin diseases, which exceeds $10 billion annually. For the last decade extensive basic science and clinical research in chronic wounds …
The Preparation Of Functional Surfaces, Philip Thomas Dirlam
The Preparation Of Functional Surfaces, Philip Thomas Dirlam
Master's Theses
Diels-Alder chemistry was utilized to manipulate the surface energy of glass substrates in reversible manner. Glass slides and capillaries were functionalized with hydrophobic dieneophiles resulting in a non-wetting surface. A retro Diels-Alder reaction facilitated by the thermal treatment of the surface’s function to cleave the hydrophobic dieneophile and resulted in the fabrication of a hydrophilic surface. Contact angle (CA) measurements were used as preliminary measurements for monitoring the changes in surface energy exhibited during the initial hydrophobic state (CA - 70±3°), after attachment of the dieneophile creating a hydrophobic state (CA - 101±9°) followed by reestablishment of the hydrophilic state …
Colloidal Microcapsules: Surface Engineering Of Nanoparticles For Interfacial Assembly, Debabrata Patra
Colloidal Microcapsules: Surface Engineering Of Nanoparticles For Interfacial Assembly, Debabrata Patra
Open Access Dissertations
Colloidal Microcapsules (MCs), i.e. capsules stabilized by nano-/microparticle shells are highly modular inherently multi-scale constructs with applications in many areas of material and biological sciences e.g. drug delivery, encapsulation and microreactors. These MCs are fabricated by stabilizing emulsions via self-assembly of colloidal micro/nanoparticles at liquid-liquid interface. In these systems, colloidal particles serve as modular building blocks, allowing incorporation of the particle properties into the functional capabilities of the MCs. As an example, nanoparticles (NPs) can serve as appropriate antennae to induce response by external triggers (e.g. magnetic fields or laser) for controlled release of encapsulated materials. Additionally, the dynamic nature …
Growth Mechanisms Of Complex Organics In The Gas Phase And On Metal Nanoparticles Generated By A Laser Vaporization Process, Abdel Rahman Soliman
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. …
Calcium Carbonate And Ammonium Polyphosphate-Based Flame Retardant Composition For Polypropylene, Sarang Deodhar, Kadhiravan Shanmuganathan, Qinguo Fan, Charles A. Wilkie, Maurius C. Costache, Nicholas A. Dembsey, Prabir K. Patra
Calcium Carbonate And Ammonium Polyphosphate-Based Flame Retardant Composition For Polypropylene, Sarang Deodhar, Kadhiravan Shanmuganathan, Qinguo Fan, Charles A. Wilkie, Maurius C. Costache, Nicholas A. Dembsey, Prabir K. Patra
Chemistry Faculty Research and Publications
The chemical mode of action as a flame retardant of calcium carbonate nanoparticles combined with ammonium polyphosphate in polypropylene was investigated. Reduction in burning rates for 0.5 mm thick samples were observed without appreciable char formation up to 30 wt % loading of additives. Thermogravimetric analysis (TGA) of the mixture of CaCO3 and ammonium polyphosphate (APP) showed that calcium carbonate nanoparticles react with ammonium polyphosphate before the degradation of the phosphate chains. TGA–FTIR studies of the polymer composite samples and powder mixtures of the additives confirmed the evolution of ammonia and carbon dioxide due to interaction between the additives. …
Detection Of Folate Binding Protein, Anwer Unnisa
Detection Of Folate Binding Protein, Anwer Unnisa
All Capstone Projects
Cancer is the second leading cause of death despite the anti cancer developments including hormone therapy, radiotherapy, chemotherapy. Chemotherapy includes use of potent drugs such as camptothecin, paclitaxel and mitomycin. These drugs have an effect which is dose responsive, where the drug exposure and cell kill are proportional. This chemotherapy is high dose and has less selectivity for cancer cells and has more toxic effect to normal cells. Such kind of non specific treatment to tumor is causing hurdles in the treatment of cancer by chemotherapy. To overcome this current limitation to chemotherapy, the anti cancer drug with high specificity …
Synthesis And Characterization Of Nanoparticulated Rifampicin, Lakshmi Sai Priyanka Guttikonda
Synthesis And Characterization Of Nanoparticulated Rifampicin, Lakshmi Sai Priyanka Guttikonda
All Capstone Projects
Rifampicin is a naturally made, non-peptide antibiotic. It is bactericidal, killing by disabling the protein expression system universally conserved by all bacteria. Specifically, it inhibits the RNA polymerase protein, which is responsible for binding to a strand of DNA as a template and using it to construct a strand of mRNA. The reason rifampicin works so well is that it is a rigid molecule, and sits tightly in the pocket where it binds, allowing the bonds to be very strong. However, this also means if an amino acid with the edge of the channel with a small side chain is …
Fabrication Of Poly(Vinylidene Fluoride) (Pvdf) Nanofibers Containing Nickel Nanoparticles As Future Energy Server Materials, Faheem A. Sheikh, Travis Cantu, Javier Macossay-Torres, Hern Kim
Fabrication Of Poly(Vinylidene Fluoride) (Pvdf) Nanofibers Containing Nickel Nanoparticles As Future Energy Server Materials, Faheem A. Sheikh, Travis Cantu, Javier Macossay-Torres, Hern Kim
Chemistry Faculty Publications and Presentations
In the present study, we introduce Poly(vinylidene fluoride) (PVDF) nanofibers containing nickel (Ni) nanoparticles (NPs) as a result of an electrospinning. Typically, a colloidal solution consisting of PVDF/Ni NPs was prepared to produce nanofibers embedded with solid NPs by electrospinning process. The resultant nanostructures were studied by SEM analyses, which confirmed well oriented nanofibers and good dispersion of Ni NPs over them. The XRD results demonstrated well crystalline feature of PVDF and Ni in the obtained nanostructures. Physiochemical aspects of prepared nano-structures were characterized for TEM which confirmed nanofibers were welloriented and had good dispersion of Ni NPs. Furthermore, the …
Engineering Nanoparticles Surface For Biosensing: "Chemical Noses" To Detect And Identify Proteins, Bacteria And Cancerous Cells, Oscar Ramon Miranda-Sanchez
Engineering Nanoparticles Surface For Biosensing: "Chemical Noses" To Detect And Identify Proteins, Bacteria And Cancerous Cells, Oscar Ramon Miranda-Sanchez
Open Access Dissertations
Rapid and sensitive detection of biomolecules is an important issue in nanomedicine. Many disorders are manifested by changes in protein levels of serum and other biofluids. Rapid and effective differentiation between normal and cancerous cells is an important challenge for the diagnosis and treatment of tumor. Likewise, rapid and effective identification of pathogens is a key target in both biomedical and environmental monitoring. Most biological recognition processes occur via specific interactions. Gold nanoparticles (AuNPs) feature sizes commensurate with biomacromolecules, coupled with useful physical and optical properties. A key issue in the use of nanomaterials is controlling the interfacial interactions of …
Characterization Of Composite Broad Band Absorbing Conjugated Polymer Nanoparticles Using Steady-State, Time-Resolve And Single Particle Spectroscopy, Maxwell Scotland Bonner
Characterization Of Composite Broad Band Absorbing Conjugated Polymer Nanoparticles Using Steady-State, Time-Resolve And Single Particle Spectroscopy, Maxwell Scotland Bonner
Electronic Theses and Dissertations
As the global economy searches for reliable, inexpensive and environmentally friendly renewable energy resources, energy conservation by means of photovoltaics has seen near exponential growth in the last decade. Compared to state-of-the-art inorganic solar cells, organic photovoltaics (OPVs) composed of conjugated polymers are particularly interesting because of their processability, flexibility and the potential for large area devices at a reduced fabrication cost. It has been extensively documented that the interchain and intrachain interactions of conjugated polymers complicate the fundamental understanding of the optical and electronic properties in the solid-state (i.e. thin film active layer). These interactions are highly dependent on …
Micro- And Nanoparticles In Uv-Cured Thin Films, T. Christopher Corkery, Joseph Chan, Mike J. Idacavage, Elizabeth R. Gillies, Paul J. Ragogna
Micro- And Nanoparticles In Uv-Cured Thin Films, T. Christopher Corkery, Joseph Chan, Mike J. Idacavage, Elizabeth R. Gillies, Paul J. Ragogna
Chemistry Presentations
No abstract provided.
Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel
Accumulation, Speciation, And Distribution Of Metal(Loids) In Plants: Applications Of Synchrotron Techniques In Environmental Sciences, Hiram Castillo-Michel
Open Access Theses & Dissertations
In the last two decades, synchrotron based techniques have gained popularity and been increasingly used in environmental sciences. The present dissertation has relied significantly in the use of synchrotron based techniques to study the speciation, coordination, and distribution of toxic metal(loids) in plants. This study included three plant species: Parkinsonia florida, Prosopis juliflora, and Zea mays. P. florida is a plant species native to the semi-desert regions of North America. The cultivation characteristics of this shrub/tree suggest that it could be used for phytoremediation purposes in semiarid regions. P. florida plants were tested for their capacity to remove arsenic (As) …
Supramolecular Organization Of Nanoparticles, Brenda M. Porta Linnell
Supramolecular Organization Of Nanoparticles, Brenda M. Porta Linnell
Open Access Theses & Dissertations
The study of supramolecular structures with nano-architectures has become an active area of research in recent years. They have the potential to generate functional materials with applications in medicine and emerging technologies. In this dissertation, the supramolecular organization of gold nanoparticles (AuNP) and other nano-scale structures such as discrete styrene-based polymers was investigated. The synthesis and characterization of metal-mediated AuNPs systems using pendant ligands on the AuNP such as 11-diethylenetriamine-undecane-1-thiol, 11-Mercapto-undecanoic acid [2-(2-amino-ethylamino)-ethyl]-amide, Bis(11-oxo-nicotinic acid, undecine)disulfide, and 11-mercaptoundecanoic acid, and using Cu(II) to mediate the formation of supramolecular AuNP systems with sizes of 200 nm ¡V 3 fÃ?m, are …
Investigations On Morphology, Spectroscopy And Near-Infrared Photoresponse Sensitization Of Conjugated Polymers In Organic Photovoltaics, Zhongjian Hu
Electronic Theses and Dissertations
Conjugated polymer architecture and morphology are two of the key factors that determine corresponding opto-electronic device performance. It is well-known that conjugated polymers display a variety of conformations and exhibit aggregation in their materials and even for individual polymer chains. The intrinsic structural heterogeneity of conjugated polymers strongly complicates the active layer morphology and phase separation, which are crucial for photoinduced charge generation and transport in polymer based bulk heterojunction-organic photovoltaics device (BHJ-OPVs). Aiming to probe the molecular level correlations between conjugated polymer architecture, morphology and optoelectronic properties, single molecule spectroscopy (SMS) and single particle spectroscopy (SPS) were employed. The …
Non Aggregated Colloidal Silver Nanoparticles For Surface Enhanced Resonance Raman Spectroscopy, Aoife Power, John Cassidy, Tony Betts
Non Aggregated Colloidal Silver Nanoparticles For Surface Enhanced Resonance Raman Spectroscopy, Aoife Power, John Cassidy, Tony Betts
Articles
Silver nanoparticles with a tuneable l max were produced as colloids by heterogeneous nucleation. The synthesis process is both fast and repeatable, producing stable PVA capped nanoparticles. The colloid’s effectiveness in the SERRS system was investigated using Rhodamine 6G, R6G, Crystal Violet, CV, and Malachite Green, MG, as probe molecules. A clear sensing trend was observed, where the Raman signal emitted was significantly enhanced by the addition of silver nanoparticles. A build up of signal intensity is observed until an optimum ratio is achieved, followed by a decline in signal intensity as the concentration of nanoparticles is further increased. The …
Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali
Localized Surface Plasmon Resonance Of Single Silver Nanoparticles Studied By Dark-Field Optical Microscopy And Spectroscopy, Wei Cao, Tao Huang, Xiao-Hong Nancy Xu, Hani E. Elsayed-Ali
Electrical & Computer Engineering Faculty Publications
Localized surface plasmon resonance (LSPR) of Ag nanoparticles (NPs) with different shapes and disk-shaped Ag NP pairs with varying interparticle distance is studied using dark-field optical microscopy and spectroscopy (DFOMS). Disk-, square-, and triangular-shaped Ag NPs were fabricated on indium tin oxide-coated glass substrates by electron beam lithography. The LSPR spectra collected from single Ag NPs within 5×5 arrays using DFOMS exhibited pronounced redshifts as the NP shape changed from disk to square and to triangular. The shape-dependent experimental LSPR spectra are in good agreement with simulations using the discrete dipole approximation model, although there are small deviations in the …