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Study On Energy Absorption Behaviors Of Hydrophobic Mesoporous Materials, Zhongyuan Sun Aug 2010

Study On Energy Absorption Behaviors Of Hydrophobic Mesoporous Materials, Zhongyuan Sun

Theses and Dissertations - UTB/UTPA

Nanoporous energy absorption system has been developed tremendously as an advanced energy storage system in recent years. This research is to optimize the mesoporous energy absorption matrixes via surface treatment to find out the optimum conditions for higher energy conversion efficiency. Five mesoporous silica matrixes with pore size in a range of 3 to 31.6 nm were investigated. Six alkylchlorosilanes were used as the modification reagents. The results showed that the energy absorption density via pressure-induced infiltration is as high as 8.0 J/g which is 100 times larger than that of conventional energy absorption materials. The controllability of the energy …


Design, Synthesis And Characterization Of Oriented Glyco-Affinity Macroligands For Glyco-Capturing, Glycomics And Glycoproteomics Applications, Srinivas Chalagalla Jan 2010

Design, Synthesis And Characterization Of Oriented Glyco-Affinity Macroligands For Glyco-Capturing, Glycomics And Glycoproteomics Applications, Srinivas Chalagalla

ETD Archive

Cell surface carbohydrates existing as parts of glycoproteins, glycolipids, and other conjugates present the first information about cell to the outside world and are intimately involved in various biological events such as intercellular communication, and molecular and cellular targeting. However, mechanisms of most processes at the molecular level are still unclear. Therefore, it is very important to develop carbohydrate-specific binding molecules for rapid, efficient, sensitive purification and accurate analysis of complex carbohydrate structures as well as their functions. Furthermore, carbohydrate-specific binding molecules can be expected to be used in medical diagnostic applications for carbohydrate biomarkers. In this thesis study, oriented …


Studies Of Nanoparticles From A Group Of Uniform Materials Based On Organic Salts (Gumbos), Aaron Tesfai Jan 2010

Studies Of Nanoparticles From A Group Of Uniform Materials Based On Organic Salts (Gumbos), Aaron Tesfai

LSU Doctoral Dissertations

Tesfai, Aaron, B.S., B.A., University of Missouri, Columbia, 2003 Doctor of Philosophy, Spring Commencement 2010 Major: Chemistry Studies of Nanoparticles from a Group of Uniform Materials Based on Organic Salts (GUMBOS) Dissertation directed by Professor Isiah M. Warner Pages in dissertation, 101. Words in abstract, 271. Ionic liquids (ILs) are defined as organic salts composed of ions with melting points at or below 100 °C. ILs have gained considerable attention because of their desirable properties such as low volatility, high thermal stability, and tunability. GUMBOS are an emergent class of organic salts, many of which are ionic liquids (ILs). However, …


Observations Of Elevated Formaldehyde Over A Forest Canopy Suggest Missing Sources From Rapid Oxidation Of Arboreal Hydrocarbons, Nicole Bouvier-Brown Jan 2010

Observations Of Elevated Formaldehyde Over A Forest Canopy Suggest Missing Sources From Rapid Oxidation Of Arboreal Hydrocarbons, Nicole Bouvier-Brown

Chemistry and Biochemistry Faculty Works

To better understand the processing of biogenic VOCs (BVOCs) in the pine forests of the US Sierra Nevada, we measured HCHO at Blodgett Research Station using Quantum Cascade Laser Spectroscopy (QCLS) during the Biosphere Effects on Aerosols and Photochemistry Experiment (BEARPEX) of late summer 2007. Four days of the experiment exhibited particularly copious HCHO, with midday peaks between 15–20 ppbv, while the other days developed delayed maxima between 8–14 ppbv in the early evening. From the expansive photochemical data set, we attempt to explain the observed HCHO concentrations by quantifying the various known photochemical production and loss terms in its …


The Use Of Fourier Transform (Ft) Surface-Enhanced Raman Scattering For Biochemical Analysis, Robert Butler Jeffers Jul 2009

The Use Of Fourier Transform (Ft) Surface-Enhanced Raman Scattering For Biochemical Analysis, Robert Butler Jeffers

Chemistry & Biochemistry Theses & Dissertations

Surface-enhanced Raman scattering (SERS) is a powerful spectroscopic technique that has created exciting opportunities in the field of bioanalytical chemistry, where it combines ultrasensitive detection of biologically relevant molecules with vibrational spectroscopy. Due to the difficulties in preparing reproducible SERS active substrates, SERS has been mainly used as a qualitative tool. In order for SERS to be utilized as a viable tool for quantitative analysis, simple, facile SERS substrates which generate clean, highly reproducible signals must be developed. This dissertation deals with the evaluation of three different methods of SERS that led to the development of a novel substrate for …


Web Based Classes For Enhancement Of Prelaboratory Lectures, Tiffany Hesser, Michael Collura Jun 2009

Web Based Classes For Enhancement Of Prelaboratory Lectures, Tiffany Hesser, Michael Collura

Chemistry and Chemical Engineering Faculty Publications

The use of web classes, such as Tegrity Campus1, as a supplement to pre laboratory reading or a replacement for pre laboratory lectures could become a standard tool in laboratory education protocol. In classes with multiple lab sections and instructors, pre laboratory lectures can lack consistency and it can be difficult to gauge the students’ level of preparation. With the ever increasing exposure to technology, students generally prefer information in a digital and multimedia form, rather than textbook readings. Therefore, this method can prove to better prepare students prior to laboratory experiments, increasing the overall understanding of the chemical reactions …


A Lab To Stemulate Undergraduate Students Into Science, Technology, Engineering And Mathematics Majors, Nicole Lynn Speelman Jan 2009

A Lab To Stemulate Undergraduate Students Into Science, Technology, Engineering And Mathematics Majors, Nicole Lynn Speelman

Browse all Theses and Dissertations

The central focus is the development and implementation of a research/lab module for first year chemistry courses. Electrochemical techniques are utilized to study oxidation and reduction reactions of neurotransmitters with a poly(2,2'-Bithiophene) modified electrode. The goal is to excite students about chemistry and encourage them to continue studies in Science, Technology, Engineering, and Mathematics (STEM) during their undergraduate education. The lab module was created for Project REEL (Research Experiences to Enhance Learning) and will be illustrated with results typically obtained by students. The experiment is inquiry-based, which includes challenging questions students have to do collaboration and research to answer, as …


Anthropogenic Osmium In Rain And Snow Reveals Global-Scale Atmospheric Contamination, Cynthia Chen, Peter N. Sedwick, Mukul Sharma Jan 2009

Anthropogenic Osmium In Rain And Snow Reveals Global-Scale Atmospheric Contamination, Cynthia Chen, Peter N. Sedwick, Mukul Sharma

OES Faculty Publications

Osmium is one of the rarer elements in seawater, with typical concentration of ≈10 x 10-15 g g-1 ( 5.3 x 10-14 mol kg-1. The osmium isotope composition (187Os/188Os ratio) of deep oceans is 1.05, reflecting a balance between inputs from continental crust (≈ 1.3) and mantle/cosmic dust (≈ 0.13). Here, we show that the 187Os/188Os ratios measured in rain and snow collected around the world range from 0.16 to 0.48, much lower than expected (>1), but similar to the isotope composition of ores (approximate to 0.2) …


Β-Diketonate, Β-Ketoiminate, And Β-Diiminate Complexes Of Difluoroboron, Felipe P. Macedo, Chengeto Gwengo, Sergey V. Lindeman, Mark D. Smith, James R. Gardinier Jul 2008

Β-Diketonate, Β-Ketoiminate, And Β-Diiminate Complexes Of Difluoroboron, Felipe P. Macedo, Chengeto Gwengo, Sergey V. Lindeman, Mark D. Smith, James R. Gardinier

Chemistry Faculty Research and Publications

A series of β-diketonate, keto(aryl)iminato, and β-bis(aryl)iminato complexes of difluoroboron, twenty in total, have been prepared to assess the impact of chelate ring and aniline substitution on the structural, electrochemical, and photophysical properties of these ubiquitous chelates. DFT (B3LYP/6-31G*) calculations supplemented the experimental results and both demonstrated that replacing oxygen with the more electron-donating aniline groups serves to only fine-tune the electronic properties because both the HOMO and LUMO energies are affected by such substitution. The electronic properties of all compounds are most greatly influenced by the nature of the substituents bound to the carbon portion of the chelate ring. …


Electrochemical Behavior Of Dill Pipe In 31%(By Mass) Nacl Solution Based New Type Inhibitor, Fu-Guo Liu, Min Du, Qing-Zhang Wang Nov 2007

Electrochemical Behavior Of Dill Pipe In 31%(By Mass) Nacl Solution Based New Type Inhibitor, Fu-Guo Liu, Min Du, Qing-Zhang Wang

Journal of Electrochemistry

The inhibitive effect of compound inhibitor including emulsifier(P), zinc sulfate, sodium polyphosphate, Glucose Gluconate was studied in 31% NaCl (by mass) solution. The inhibitory mechanism was analyzed by polarization curve and EIS. The results showed that the compound inhibitor was anodic-type inhibitor and its inhibitive effect on anodic and cathodal reaction was the most obvious at 200×10-6g·L-1. And the results of EIS revealed that the inhibition efficiency increased and the film formed on electrode surface was more and more compact with time. Inhibition mechanism was different with concentration of inhibitor.


A Computational Chemistry Study Of Spin Traps., Jacob Fosso-Tande Aug 2007

A Computational Chemistry Study Of Spin Traps., Jacob Fosso-Tande

Electronic Theses and Dissertations

Many defects in physiological processes are due to free radical damage: reactive oxygen species, nitric oxide, and hydroxyl radicals have been implicated in the parthenogenesis of cancer, diabetes mellitus, and rheumatoid arthritis. We herein characterize the phenyl-N-ter-butyl nitrone (PBN) type spin traps in conjunction with the most studied dimethyl-1-pyrroline-N-oxide (DMPO) type spin traps using the hydroxyl radical. In this study, theoretical calculations are carried out on the two main types of spin traps (DMPO and PBN) at the density functional theory level (DFT). The energies of the optimized structures, hyperfine calculations in gaseous and aqueous phases of the spin traps …


Hadron Models And Related New Energy Issues, Florentin Smarandache Jan 2007

Hadron Models And Related New Energy Issues, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The present book covers a wide-range of issues from alternative hadron models to their likely implications in New Energy research, including alternative interpretation of lowenergy reaction (coldfusion) phenomena. The authors explored some new approaches to describe novel phenomena in particle physics. M Pitkanen introduces his nuclear string hypothesis derived from his Topological Geometrodynamics theory, while E. Goldfain discusses a number of nonlinear dynamics methods, including bifurcation, pattern formation (complex GinzburgLandau equation) to describe elementary particle masses. Fu Yuhua discusses a plausible method for prediction of phenomena related to New Energy development. F. Smarandache discusses his unmatter hypothesis, and A. Yefremov …


Solvent Targeting, Avoidance And Recovery Trials (Start), Kealan Allen Jan 2006

Solvent Targeting, Avoidance And Recovery Trials (Start), Kealan Allen

Theses

Solvent is the largest-volume raw material used at Janssen Pharmaceutical (Ire) Ltd. Over 2.2 million m3 were used in 2004. The top 13 solvents make up 99% of this amount. There are two main uses for solvent on site, processing and cleaning. Processing uses 55% of the total solvent used on site, cleaning uses the remainder.

Waste solvent forms the majority of the hazardous waste produced at Janssen. Three treatment options exist at present for this waste: incineration, recovery for reuse and energy recovery. All of the hazardous waste produced on site must be exported for these treatment options, …


Solution-Based Synthesis Of Nitride Fuels, Kenneth Czerwinski, Thomas Hartmann Jan 2006

Solution-Based Synthesis Of Nitride Fuels, Kenneth Czerwinski, Thomas Hartmann

Fuels Campaign (TRP)

A wide variety of fuel concepts are considered for advanced reactor technology including metals, metal oxides or metal nitrides as solid solutions or composite materials. Nitride fuels have appropriate properties for advanced fuels including high thermal conductivity, thermal stability, solid-state solubility of actinides, fissile metal density, and suitable neutronic properties. A drawback of nitride fuels involves their synthesis. A key parameter for preparing oxide fuels is the precipitation step in the sol-gel process. For nitride fuels, the current synthetic route is carbothermic reduction from the oxide to the nitride. This process step is based on solid phase reactions and for …


Synthesis Of Vic-Dioxime Derivatives With Hydrazone Side Groups And Their Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli Jan 2006

Synthesis Of Vic-Dioxime Derivatives With Hydrazone Side Groups And Their Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli

Turkish Journal of Chemistry

Two novel vic-dioxime (L^1H_2, L^2H_2) compounds bearing hydrazone side groups and their transition metal complexes Ni(II), Co(II), Cu(II), and Zn(II) were synthesized. The vic-dioxime ligands bearing hydrazone side groups were synthesized by reacting anti-glyoximehydrazine (GH_2) with 4-nitroacetophenone and 4-methylacetophenenone, respectively. Ligands form mononuclear complexes [(LH)_2M] with a metal to ligand ratio of 1:2 with M=Co(II)(H_2O)_2, Ni(II), and Cu(II). Zn(II) forms complexes [(LH)(H_2O)(Cl)Zn] with a metal to ligand ratio of 1:1. The Co(II) complexes of the ligands are proposed to be octahedral with water molecules as axial ligands, the Ni(II) and Cu(II) complexes are proposed to be square planar, and the …


Atr-Ftir Spectroscopic Analysis Of Sorption Of Aqueous Analytes Into Polymer Coatings Used With Guided Sh-Saw Sensors, Yolanda K. Jones, Zhonghui Li, Michael M. Johnson, Fabien Josse, Jeanne Hossenlopp Dec 2005

Atr-Ftir Spectroscopic Analysis Of Sorption Of Aqueous Analytes Into Polymer Coatings Used With Guided Sh-Saw Sensors, Yolanda K. Jones, Zhonghui Li, Michael M. Johnson, Fabien Josse, Jeanne Hossenlopp

Chemistry Faculty Research and Publications

Attenuated total internal reflectance Fourier transform infrared (ATR-FTIR) spectroscopy was used for the investigation of sorption of aqueous solutions of analytes into polymer coatings. A series of simple model polymers, such as poly(dimethylsiloxane), poly(epichlorhydrin), and poly(isobutylene), and films and analytes, such as aqueous solutions of ethylbenzene, xylenes, toluene, and nitrobenzene, were used to evaluate the use of ATR-FTIR spectroscopy as a screening tool for sensor development. The ratios of integrated infrared absorption bands provided a simple and efficient method for predicting trends in partition coefficients. Responses of polymer-coated guided shear horizontal surface acoustic wave (SH-SAW) sensor platforms to the series …


Comprehensive Laboratory Measurements Of Biomass-Burning Emissions: 2. First Intercomparison Of Open-Path Ftir, Ptr-Ms, And Gc-Ms/Fid/Ecd, Ted J. Christian, B. Kleiss, Robert J. Yokelson, R. Holzinger, P. J. Crutzen, Wein Min Hao, T. Shirai, Donald R. Blake Jan 2004

Comprehensive Laboratory Measurements Of Biomass-Burning Emissions: 2. First Intercomparison Of Open-Path Ftir, Ptr-Ms, And Gc-Ms/Fid/Ecd, Ted J. Christian, B. Kleiss, Robert J. Yokelson, R. Holzinger, P. J. Crutzen, Wein Min Hao, T. Shirai, Donald R. Blake

Chemistry and Biochemistry Faculty Publications

No abstract provided.


Synthesis Of The Novel Crown Ether 1 ,9-Dioxa-4,6-Dithiacycloundecane, Cassie Booth Jan 2004

Synthesis Of The Novel Crown Ether 1 ,9-Dioxa-4,6-Dithiacycloundecane, Cassie Booth

Capstone Research Projects

Attempts to produce novel crowns, incorporating a thioacetal fragment, were made via two synthetic pathways. Despite the well-established reactions found in path A (see figure 3), this method failed to produce the desired crown. Path B, a one-pot reaction originally designed to close rings via the addition of a thioacetal fragment, yielded an oily product that was purified with a silica gel column (48.3% yield). Initial analysis by 1H NMR showed a structure consistent with that of the desired crown (figure 2). Mass spectroscopy was used to verify product identity, confirming the creation of our target molecule 1 ,9-dioxa-4,6-dithiacycloundecane.


Redox Reactions Of The Pyranopterin System Of The Molybdenum Cofactor, Sharon J. Nieter Burgmayer, Dori L. Pearsall, Shannon M. Blaney, Eva M. Moore, Calies Sauk-Schubert Jan 2004

Redox Reactions Of The Pyranopterin System Of The Molybdenum Cofactor, Sharon J. Nieter Burgmayer, Dori L. Pearsall, Shannon M. Blaney, Eva M. Moore, Calies Sauk-Schubert

Chemistry Faculty Research and Scholarship

This work provides the first extensive study of the redox reactivity of the pyranopterin system that is a component of the catalytic site of all molybdenum and tungsten enzymes possessing molybdopterin. The pyranopterin system possesses certain characteristics typical of tetrahydropterins, such as a reduced pyrazine ring; however, it behaves as a dihydropterin in redox reactions with oxidants. Titrations using ferricyanide and dichloroindophenol (DCIP) prove a 2e(-)/2H(+) stoichiometry for pyranopterin oxidations. Oxidations of pyranopterin by Fe(CN)(6)(3-) or DCIP are slower than tetrahydropterin oxidation under a variety of conditions, but are considerably faster than observed for oxidations of dihydropterin. The rate of …


Electronic Structural Investigations Of Bi- And Polymetallic Complexes Using Quantum Mechanical Methods, Zakiya Sheni Wilson Jan 2004

Electronic Structural Investigations Of Bi- And Polymetallic Complexes Using Quantum Mechanical Methods, Zakiya Sheni Wilson

LSU Doctoral Dissertations

Understanding the dynamics influencing chemical reactivity is essential for properly exploiting matter into more useful purposes. In that manner, computational chemistry is a tool frequently used to study chemical properties at the most intimate level, i.e. the single molecule.

With this work, we probe the chemistry governing a variety of multi-faceted bi- and polymetallic compounds. To date our research consists of four major projects: bimetallic rhodium-catalyzed hydroformylation and aldehyde-water shift hydrocarboxylation catalysis; a novel linear M-H-M interaction in a bridged bis(dialkylphosphino)methane complex of nickel; and CeBe13, a heavy fermion conductor. Computational investigations on these systems allow us to …


The Effects Of Computer Animations On Secondary Students’ Understanding Of The Crushing Can Chemical Demonstration, Resa Marie Kelly Jan 2000

The Effects Of Computer Animations On Secondary Students’ Understanding Of The Crushing Can Chemical Demonstration, Resa Marie Kelly

Dissertations and Theses @ UNI

Understanding chemistry requires the ability to think at three different levels: submicrochemistry, macrochemistry, and representational chemistry. Students often have difficulty making connections among these three areas due to the abstract nature of many chemistry concepts. The purpose of this paper is to investigate how computer animations affected secondary students' understanding of the Crushing Can Demonstration. This investigation compared two groups of chemistry students at a large, suburban high school. The treatment group viewed the animation after seeing and discussing the crushing can demonstration, while the control group received the same instruction as the treatment group but did not see the …


Portfolio Assessment In High School Chemistry, Mark M. Laporte Jan 1999

Portfolio Assessment In High School Chemistry, Mark M. Laporte

Dissertations and Theses @ UNI

This is a report of one high school chemistry teacher's experience of implementing portfolio assessment in his classroom. This project was carried out using a teacher as researcher model. The chemistry classes were p1imarily composed of 11th grade students in a rural midwestern high school setting. This thesis reviews some of the literature regarding alternative assessment focusing particularly on the literature related to portfolio assessment. The chemistry portfolio design is explained in detail including a rationale for each of the portfolio elements. The teacher developed nine portfolio elements of which the students were required to complete five. The nine elements …


Development Of Solid Phase Microextraction Methods For Contraband Drugs, Vangielynn Cruz Tersol Apr 1997

Development Of Solid Phase Microextraction Methods For Contraband Drugs, Vangielynn Cruz Tersol

Chemistry & Biochemistry Theses & Dissertations

The objective of this study is to develop analytical methods for studying contraband drugs at nanogram levels and to demonstrate the utility of the methods. A method which combines solid phase microextraction with ion mobility spectrometry (SPME-IMS) was developed. The SPME-IMS method was used as a rapid screening tool in studying the chemistry of cocaine HCI, heroin HCI, and heroin freebase on surfaces. The total time for sample preparation, reaction, and analysis is approximately seven minutes. Another method that was developed is one that combines solid phase microextraction with gas chromatography (SPME-GC) for the quantitative analysis of cocaine freebase and …


Atomic And Molecular-Perspectives In Electrochemical Interfaces, Zhaowu Tian Feb 1995

Atomic And Molecular-Perspectives In Electrochemical Interfaces, Zhaowu Tian

Journal of Electrochemistry

The following recent studies on the atomic and molecular-perspectives at electrochemical interfaces using Raman, IR, STM and quantum chemical methed by electrochemistry group in Xiamen University are briefly reviewed. 1.Orientation, charge transfer and bonding of adsorbed molecules. 2. Adsorption effect, electrode potential effect and adatom effect on the electron populations and strength of intramolec ular bonds of the adsorbed molecules. 3. Detailed classification into various types (e. g., competitive, chemically inductive, physical inductive etc.) of coadsorption on electrodes according to the above-mentioned effects.  4. Single crystal face structure effect and adatom effect on the kinetics and the mechanisms of electrocatalytic …


Electrochemical Studies Of Swelling And Shrinking Of Clay Films, Jia Du Jan 1993

Electrochemical Studies Of Swelling And Shrinking Of Clay Films, Jia Du

Master's Theses

No abstract provided.


Ua66/7/2 Hilltopper News, Wku Chemistry Oct 1990

Ua66/7/2 Hilltopper News, Wku Chemistry

WKU Administration Documents

Newsletter created by and about the WKU Chemistry department.


The Chemistry Of Sulfonyl Fluorides: Sf5 And/Or So2f Containing Compounds As Precursors To Sulfonic Acids, Robin Joyce Terjeson Jan 1989

The Chemistry Of Sulfonyl Fluorides: Sf5 And/Or So2f Containing Compounds As Precursors To Sulfonic Acids, Robin Joyce Terjeson

Dissertations and Theses

Sulfonyl fluoride systems and their derivatives, RS02F, where R represents hydrocarbon/fluorocarbon moieties continue to be of considerable interest. The incorporation of the sulfonyl fluoride group (S02F) into molecular systems can lead to compounds that are useful as ion-exchange resins, surface active agents, fuel cell electrolytes, and strong sulfonic acids/salts.

Interest in preparing SF5 containing sulfonyl fluorides led to the synthesis of the ᵝ-sultone, SF5CHCF20S02, and its rearranged product. Hydrolysis of the sultone gave SF5CH2S02F which led to the sulfonic acid and salt, SF …


Analytical Chemistry Applications Of Synchrotron Radiation, Juana Acrivos Jan 1988

Analytical Chemistry Applications Of Synchrotron Radiation, Juana Acrivos

Faculty Publications, Chemistry

Lecture given at the University of California at Berkeley as NSF Woman Chemistry Professor.


Chemistry, Norman Kulevsky Jan 1983

Chemistry, Norman Kulevsky

UND Departmental Histories

This departmental history was written on the occasion of the UND Centennial in 1983.


A Study Of Selected Variables For Prediction Of Success And Placement In General Chemistry At Western Michigan University, Stephen M. Yekeson Dec 1975

A Study Of Selected Variables For Prediction Of Success And Placement In General Chemistry At Western Michigan University, Stephen M. Yekeson

Dissertations

Chapter I

The Problem

Introduction

The traditional philosophy that a college-or a university is an exclusive institution in which only highly selected individuals receive a concentrated training in the traditional liberal arts no longer exists. In America, for instance, as early as 1870, Harvard, the colonial college with a narrow curriculum, was transformed rather rapidly into a modern university with many new subjects and the elective system (Garrett, 1949). Also, since 1642, when the first entrance requirements were instituted for American higher education, a continuing debate has developed over what constitutes a sound curriculum for education. There are those who …