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Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, Joshua Erold Robert Abelard 2010 College of William & Mary - Arts & Sciences

Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, Joshua Erold Robert Abelard

Dissertations, Theses, and Masters Projects

No abstract provided.


Sulfated Zirconia Modified Sba-15 Catalysts For Cellobiose Hydrolysis, Volkan Degirmenci, Deniz Uner, Basak Cinlar, Brent H. Shanks, Aysen Yilmaz, Rutget A. van Santen, Emiel J. M. Hensen 2010 Middle East Technical University

Sulfated Zirconia Modified Sba-15 Catalysts For Cellobiose Hydrolysis, Volkan Degirmenci, Deniz Uner, Basak Cinlar, Brent H. Shanks, Aysen Yilmaz, Rutget A. Van Santen, Emiel J. M. Hensen

Chemical and Biological Engineering Publications

Zirconia modified SBA-15 becomes a very active catalyst for the selective hydrolysis of cellobiose to glucose after sulfation. Spectroscopic investigations indicate the presence of Brønsted acid sites with similar properties to those present in conventional sulfated zirconia. Indications are found that the sulfate groups attached to zirconia interact with silanol groups of SBA-15. The catalytic activity in cellobiose hydrolysis correlates well with results for temperature-programmed decomposition of i-propylamine for a range of sulfated ZrO2/SBA-15 catalysts. A glucose yield of 60% during cellobiose hydrolysis at a reaction time of 90 min at 160° C is obtained.


Energy Of The Conduction Band In Near Critical Point Fluids, Cherice M. Evans, G. L. Findley 2010 CUNY Queens College

Energy Of The Conduction Band In Near Critical Point Fluids, Cherice M. Evans, G. L. Findley

Publications and Research

The study of the evolution of the conduction band in dense gases and supercritical fluids near the critical point has been complicated by a lack of precise experimental measurements. Both photoemission from an electrode immersed in the fluid and field ionization of a molecule doped into the fluid have been used to probe solvent density effects on the energy of an excess electron as a function of fluid number density and temperature. In this perspective, we present recent experimental results that show a strong critical point effect on the minimumconduction band energy near the critical density and temperature of a ...


Synthesis Of Novel Glycosylidene-Based Quinolines, Peter H. Dobbelaar 2010 Seton Hall University

Synthesis Of Novel Glycosylidene-Based Quinolines, Peter H. Dobbelaar

Seton Hall University Dissertations and Theses (ETDs)

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Hydrophobic Silicas With Well-Defined Chemistry And Geometry: Synthesis, Adsorption, And Interfacial Properties, Francis Bernardoni 2010 Seton Hall University

Hydrophobic Silicas With Well-Defined Chemistry And Geometry: Synthesis, Adsorption, And Interfacial Properties, Francis Bernardoni

Seton Hall University Dissertations and Theses (ETDs)

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Technology For The Organic Chemist: Three Exploratory Modules, John J. Esteb, LuAnne M. McNulty, John Magers, Paul Morgan 2010 Butler University

Technology For The Organic Chemist: Three Exploratory Modules, John J. Esteb, Luanne M. Mcnulty, John Magers, Paul Morgan

Scholarship and Professional Work - LAS

The ability to use computer-based technology is an essential skill set for students majoring in chemistry. This exercise details the introduction of appropriate uses for this technology in the organic chemistry series. The incorporation of chemically appropriate online resources (module 1), scientific databases (module 2), and the use of a chemical drawing program (module 3) are detailed here.


Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori 2010 University of Texas at El Paso

Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori

Open Access Theses & Dissertations

Water pollution is major environmental problem worldwide. Many common industrial organic compounds that make their way into water systems can be carcinogenic at trace levels and are difficult and costly to remove completely with conventional technologies. Because of this, authorities and researchers are trying to improve current water cleanup techniques.

Heterogeneous photocatalysts that accelerate the photocatalytic destruction of organic contaminants in water are a potentially inexpensive and highly effective way to remove both trace-level and saturated harmful compounds from industrial waste streams and drinking water. Titanium dioxide has the potential to completely mineralize organic compounds in water under ultraviolet light ...


Physical And Biochemical Assessment Of Mexican Palo Verde Response To Chromium Toxicity, Yong Zhao 2010 University of Texas at El Paso

Physical And Biochemical Assessment Of Mexican Palo Verde Response To Chromium Toxicity, Yong Zhao

Open Access Theses & Dissertations

In the United States, about 1/3 of the 1400 superfund sites have been reported to be chromium contaminated, making chromium the second most common metal found in superfund chemical contamination sites. Chromium removal from soil has commonly been carried out via chemical, physical, and thermal processes. However, these methods are expensive and/or invasive to local ecosystems. In contrast to these techniques, phytoremediation (the use of plants to remove toxic substances from areas containing contamination at low or medium levels) appears to be a cost-effective and environmentally friendly process for chromium removal. However, most reports on chromium phytoremediation suggest ...


Synthesis And Manufacture Of Photocrosslinkable Poly(Caprolactone)-Based 3d Scaffolds For Tissue Engineering Applications, Nathan Jonathan Castro 2010 University of Texas at El Paso

Synthesis And Manufacture Of Photocrosslinkable Poly(Caprolactone)-Based 3d Scaffolds For Tissue Engineering Applications, Nathan Jonathan Castro

Open Access Theses & Dissertations

It is known that the body can efficiently repair hard tissue (bone) micro fractures by suturing the defect through the deposition of minerals resulting in an area that is stronger post-injury. Larger defects, however, generally cause more trouble since the body is incapable of repairing them. Bone defects can occur as a result of congenital abnormalities, trauma, or disease. Traditional methods for addressing these defects have involved the use of acellular cadaverous bone or autologous bone. Both contain innate problems associated with them; the former method can result in disease transmission, as well as very low integration with the host ...


A New Photochemical Method For The Preparation Of Amino Acid-α-Phenylthioesters And Peptide-α-Phenylthioesters, Tyrone Hogenauer 2010 University of Texas at El Paso

A New Photochemical Method For The Preparation Of Amino Acid-α-Phenylthioesters And Peptide-α-Phenylthioesters, Tyrone Hogenauer

Open Access Theses & Dissertations

We describe the development of a novel resin with a photoreactive N-acylnitroindoline linker that allows for the synthesis of amino acid- (in solution) or peptide-α-thioesters using standard Fmoc/t-Bu standard solid phase peptide synthesis (SPPS). Recent advances have shown that the yields of this thioesterification reaction have dramatically increased due to a simple change in the order of addition of reagents. Upon illumination with UV-light, in the presence of N-hydroxybenzotriazole (HOBt), the amino acid- or peptide-α-OBt ester is generated by direct photo-release from the nitroindoline linker with minimal epimerization, followed by reaction with thiophenol in the dark to produce amino ...


Iron And Manganese Based Nanomaterials For The Removal Of Selenite And Selenate From Aqueous Solution, Christina Marie Gonzalez 2010 University of Texas at El Paso

Iron And Manganese Based Nanomaterials For The Removal Of Selenite And Selenate From Aqueous Solution, Christina Marie Gonzalez

Open Access Theses & Dissertations

Selenium, a naturally occurring element in the environment, is an essential nutrient for humans and animals. However, there is a narrow range between selenium deficiency and toxicity. Selenium in natural waters generally has a concentration of < 10 ppb (parts per billion); however, in the San Joaquin Valley of California concentrations of selenium ranging from 140 to 1400 ppb have been observed. Anthropogenic practices such as agricultural irrigation drainage, coal burning power plants, combustion of fossil fuels, and mining operations are increasing selenium concentrations in aqueous environments. Once in aqueous environments, selenium exists primarily as the two inorganic oxoanions selenite (SeO32-) and selenate (SeO42-). Both of these selenium oxoanions are known to bioaccumulate and can cause embryotoxic and teratogenic effects to waterfowl. There has been a variety of treatment technologies developed for remediation of both selenium oxoanions in water including bacterial reduction, membrane filtration, chemical reduction, reverse osmosis, and solar ponds. However, these treatment technologies are not cost efficient. In this study an alternative treatment technique known as adsorption was used with three synthetic nanomaterials consisting of an iron oxide, manganese oxide, and an iron/manganese oxide. The pH profiles, time dependencies, competitive anion effects, and adsorption isotherms were performed with each of the nanomaterials for both selenite and selenate. In addition, X-ray absorption spectroscopy (XAS) studies were performed to determine both the oxidation state and binding coordination of the selenium oxoanion binding to the nanomaterials.

The investigation revealed the non microwave-assisted and microwave-assisted synthetic Fe3O4 and Mn3O4 nanomaterials, as well as the non microwave-assisted synthetic MnFe2O4 nanomaterial had the phases of magnetite, hausmannite, and Jacobsite, while the grain sizes were 27, 25, 25, 34, and 27 nm, respectively. The optimal binding of selenium oxoanions for all nanomaterials examined was reached at pH 4. Both non microwave-assisted and microwave-assisted Fe3O4 ...


Chromium(Iii/Vi) Binding To Magnetite (Fe3o4), Hausmannite (Mn3o4), And Jacobsite (Mnfe2o4) Nanomaterials, Jeffrey Edward Hernandez 2010 University of Texas at El Paso

Chromium(Iii/Vi) Binding To Magnetite (Fe3o4), Hausmannite (Mn3o4), And Jacobsite (Mnfe2o4) Nanomaterials, Jeffrey Edward Hernandez

Open Access Theses & Dissertations

Chromium is a very versatile metal that is used for many applications in the world. Two of the most common ions of chromium that occur naturally are Cr(III) and Cr(VI). These two oxidation states have very different heath effects in living organisms. Cr(III) is relatively non-toxic to living organisms; however, Cr(VI) is very toxic to most living organisms This study was conducted to find a simple and cost effective method to sequester these two common ionic species of chromium from sources of water that are adjacent to or that are affected by other water sources contaminated ...


Study Of Pbdes In Wastewater, Water And Sludge Of El Paso Del Norte Border Region Using Sbse Td/Gc-Ms, Beatriz Adriana Rocha-Gutierrez 2010 University of Texas at El Paso

Study Of Pbdes In Wastewater, Water And Sludge Of El Paso Del Norte Border Region Using Sbse Td/Gc-Ms, Beatriz Adriana Rocha-Gutierrez

Open Access Theses & Dissertations

Polybrominated diphenyl ethers (PBDEs) are a group of brominated compounds widely used as flame retardants. PBDEs are structurally similar to polychlorinated biphenyls (PCBs), and appear to act similarly in the environment. Due to their persistence and lipophilicity, PBDEs are found to be bioaccumulated and biomagnified in the food chain. Current research in PBDEs is focused on their occurrences, concentration, fate and transport in the environment, and the impact in the ecosystem and human health. Since PBDEs are not regulated in the USA, large amounts of these harmful chemicals are being dumped indiscriminately into the drainage system. As a result, these ...


Approaches Towards The Synthesis Of Bradyoxetin, Vanildo Martins Lima Braga 2010 University of Mississippi

Approaches Towards The Synthesis Of Bradyoxetin, Vanildo Martins Lima Braga

Electronic Theses and Dissertations

Quorum sensing bacteria produce and release chemical signal molecules (like N-acyl homoserine lactones, AHL) that increase in concentration as a function of cell density. The responses cover a large spectrum of process such as the virulence in Staphylococcus aureus, competence for DNA-uptake in Bacillus subtilis and Streptococcus pneumoniae, sporulation in Bacillus subtilis, conjugal plasmid transfer in Enterococcus faecalis, and bacteriocin production in lactic acid bacteria. The collapse of (AHL) signaling system in bacteria represents an attractive therapeutic approach towards the development of new antibiotics. Recently, a new extracellular modulator was isolated from a symbiotic bacterium (Bradyrhizobium japonicum) that nodulates soybean ...


Developing The Techniques For Raman, Surface-Enhanced Raman Scattering (Sers), And Fluorescence Spectroscopies Of Organic Molecules In Isolation, Jonathan Wolfe 2010 University of Mississippi. Sally McDonnell Barksdale Honors College

Developing The Techniques For Raman, Surface-Enhanced Raman Scattering (Sers), And Fluorescence Spectroscopies Of Organic Molecules In Isolation, Jonathan Wolfe

Honors Theses

The nature of matter and light has been a subject of philosophical debate since antiquity. However, by the end of the nineteenth century, much of the scientific community believed that most of the significant principles that govern the natural world had been discovered. Classical physics was able to explain complex phenomena such as planetary motions, elasticity, and hydrodynamics. The field of thermodynamics had been developed nearly to completion by James Joule, Sadi Carnot, Josiah Gibbs, et al. The magnetic and electronic nature of light had been demonstrated by James Clerk Maxwell's famous equations. In the neighboring field of chemistry ...


Synthesis Of Analogues Based On The Opioid Alkaloid Mitragynine, Marco A. Arribas 2010 University of Mississippi

Synthesis Of Analogues Based On The Opioid Alkaloid Mitragynine, Marco A. Arribas

Electronic Theses and Dissertations

Opioid analgesics such as morphine and its derivatives are the most frequently prescribed narcotics for the treatment of severe and chronic pain. Among other side effects caused by the administration of these opioid analgesics, physical dependence and addiction are the most undesirable ones. Currently, pharmacological approaches to treat opioid dependence include mainly methadone and LAAM (mu-agonists), buprenorphine (mu-partial agonist) and clonidine (alpha2-adrenergic agonist). Considering the negative aspects of the relapsing nature correlated to opioid dependence, it is important to search for new ways to overcome this problem. The scope of this work is to study novel compounds based on the ...


Development Of A Laser-Induced Breakdown Spectrometer For Lead-Free Gunshot Residue Analysis, Ryan Alexander Gregg 2010 University of Mississippi. Sally McDonnell Barksdale Honors College

Development Of A Laser-Induced Breakdown Spectrometer For Lead-Free Gunshot Residue Analysis, Ryan Alexander Gregg

Honors Theses

Research has demonstrated that Laser‐Induced Breakdown Spectroscopy (LIBS) can be used as an effective method of screening for the common elemental components in gunshot residue. Barium (Ba), lead (Pb), and antimony (Sb) make up the primer cap of most ammunition involved in forensic gunshot residue analysis. Recently, ammunition manufacturers have started producing and popularizing ammunition with zinc (Zn), titanium (Ti), and gadolinium (Gd) primer components that are non‐toxic to the environment. This paper discusses the development of the Ole Miss Department of Chemistry and Biochemistry's first LIBS instrument for forensic analysis of lead‐free using Gd as ...


Technology For The Organic Chemist: Three Exploratory Modules, John Esteb, LuAnne McNulty, John Magers, Paul Morgan, Anne Wilson 2009 Butler University

Technology For The Organic Chemist: Three Exploratory Modules, John Esteb, Luanne Mcnulty, John Magers, Paul Morgan, Anne Wilson

John Esteb

The ability to use computer-based technology is an essential skill set for students majoring in chemistry. This exercise details the introduction of appropriate uses for this technology in the organic chemistry series. The incorporation of chemically appropriate online resources (module 1), scientific databases (module 2), and the use of a chemical drawing program (module 3) are detailed here.

Note: Link is to the article in a subscription database available to users affiliated with Butler University. Appropriate login information will be required for access. Users not affiliated with Butler University should contact their local librarian for assistance in locating a copy ...


Excited Electronic States Of Auf, Elissa Butler, Benjamin Knurr, Kara Manke, Tyson Vervoort, Thomas Varberg 2009 Macalester College

Excited Electronic States Of Auf, Elissa Butler, Benjamin Knurr, Kara Manke, Tyson Vervoort, Thomas Varberg

Thomas D. Varberg

No abstract provided.


Bismuth(Iii) Triflate Catalyzed Allylation Of Cyclic Acetals And Dithianes Followed By In Situ Derivatization To Generate Highly Functionalized Esters, Ram Mohan, Scott Krabbe, Matthew Spafford 2009 Illinois Wesleyan University

Bismuth(Iii) Triflate Catalyzed Allylation Of Cyclic Acetals And Dithianes Followed By In Situ Derivatization To Generate Highly Functionalized Esters, Ram Mohan, Scott Krabbe, Matthew Spafford

Ram S. Mohan

No abstract provided.


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