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Chemistry

South Dakota State University

2017

Articles 1 - 13 of 13

Full-Text Articles in Physical Sciences and Mathematics

Lignin Transformation And Characterization Of Pyrolytic Products, Eric Amo Boakye Jan 2017

Lignin Transformation And Characterization Of Pyrolytic Products, Eric Amo Boakye

Electronic Theses and Dissertations

Lignocellulosic materials derived from plants have the ability to serve as feedstocks in place of depleting petroleum and coal for production of fuels and chemicals. Lignin forms about 30% of lignocellulosic material, and is the second most abundant non-fossil organic carbon source in the biosphere. However, it is often treated as waste or, in some instances, burned to supply energy. Developing an efficient and environmentally benign method to convert lignin to high value-added aromatic monomers (e.g., guaiacol, vanillin, acetovanillone, and eugenol) for synthesis of polymers is of interest. Mineral bases, such as NaOH and CsOH, or supported-metal catalysts (Pt, Ru, …

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Design, Synthesis And Biological Evaluation Of Novel Estradiol-Triazole Analogs Targeting Epidermal Growth Factor Receptors In Colorectal Cancer, Faez Alotaibi Jan 2017

Design, Synthesis And Biological Evaluation Of Novel Estradiol-Triazole Analogs Targeting Epidermal Growth Factor Receptors In Colorectal Cancer, Faez Alotaibi

Electronic Theses and Dissertations

Colorectal cancer is a life threatening and second cause of death from cancer in the United States. Several proteins (molecular targets) are highly expressed in Colorectal cancer (CRC). Among these molecular targets is Epidermal Growth Factor Receptors (EGFRs) which are overexpressed in cancer cells. Targeting and blocking the downstream signaling could lead to cease cell proliferation and division and hence control the spread of the disease. Molecular modeling is a powerful tool in drug discovery, which has been utilized to design many drug candidates that exhibit biological effect in many disease including cancer. Additionally, pharmacophores such as 1,2,3-triazole showed potency …

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Analysis Of Novel Cyanide Antidote Dimethyl Trisulfide For Pharmacokinetic Studies, And Sulfur Mustard Metabolites For Identification Of Biomarker Of Inhaled Dose, Erica Manandhar Jan 2017

Analysis Of Novel Cyanide Antidote Dimethyl Trisulfide For Pharmacokinetic Studies, And Sulfur Mustard Metabolites For Identification Of Biomarker Of Inhaled Dose, Erica Manandhar

Electronic Theses and Dissertations

Cyanide poisoning by accidental or intentional exposure poses a severe health risk. The current FDA approved antidotes for cyanide poisoning can be effective, but each suffers from specific major limitations. Dimethyl trisulfide (DMTS), a sulfur donor that detoxifies cyanide by converting it into thiocyanate, is a promising next generation cyanide antidote. Although a validated analytical method to analyze DMTS is not currently available from any matrix, one will be vital for the approval of DMTS as a therapeutic agent against cyanide poisoning. Hence, a stir bar sorptive extraction (SBSE) gas chromatography – mass spectrometry (GC-MS) method was developed and validated …

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Design, Synthesis And Biological Screening Of Novel Cucsinspired Estrone Analogues Towards Treatment Of Hepatocellular Carcinoma, Mater Hussen Mahnashi Jan 2017

Design, Synthesis And Biological Screening Of Novel Cucsinspired Estrone Analogues Towards Treatment Of Hepatocellular Carcinoma, Mater Hussen Mahnashi

Electronic Theses and Dissertations

Cucurbitacins (CUCS) are natural products with highly oxygenated tetracyclic triterpenes produced mostly by Cucurbitaceae family plant. They are known for their therapeutic efficiency with different biological activities, such as anti-inflammatory, hepatoprotective and anti-cancer. Hepatocellular carcinoma (HCC) is the third leading cause of death worldwide. Previous reports have shown the ability of CUCS to inhibit the growth of hepatocellular carcinoma cell lines (HepG-2) significantly. Structural activity relationship studies suggested the potential of the 23, 24 enone side chain of CUCS to bind to the Epidermal Growth Factor Receptor (EGFR). Due to the limited quantities of CUCS upon isolation and the challenges …

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The Analysis Of Flavor Compounds In Green Tea Using Ice Concentration Linked With Extractive Stirrer (Icecles), Abdullah H. Alluhayb Jan 2017

The Analysis Of Flavor Compounds In Green Tea Using Ice Concentration Linked With Extractive Stirrer (Icecles), Abdullah H. Alluhayb

Electronic Theses and Dissertations

Sample preparation of target components from food samples is one of the most difficult steps in this type of analysis. Many extraction techniques have been used for this purpose, such as liquid-liquid extraction (LLE), accelerated solvent extraction (ASE), microwave-assisted extraction (MAE), solid-phase extraction (SPE), solid-phase microextraction (SPME), and stir bar sorptive extraction (SBSE). Although each of these techniques works well, they each have a number of disadvantages, including selectivity, relatively high cost, long preparation time, and matrix effects. Ice concentration linked with extractive stirrer (ICECLES) is a promising new sample preparation technique, especially for the extraction of relatively polar compounds, …

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The Relationship Between Recollection, Knowledge Transfer, And Student Attitudes Towards Chemistry, Oluwatobi Omobonike Odeleye Jan 2017

The Relationship Between Recollection, Knowledge Transfer, And Student Attitudes Towards Chemistry, Oluwatobi Omobonike Odeleye

Electronic Theses and Dissertations

Certain foundational concepts, including acid-base theory, chemical bonding and intermolecular forces (IMFs), appear throughout the undergraduate chemistry curriculum. The level of understanding of these foundational concepts influences the ability of students to recognize the relationships between sub-disciplines in chemistry. The purpose of this study was to investigate the relationship between student attitudes towards chemistry and their abilities to recollect and transfer knowledge of IMFs, a foundational concept, to their daily lives as well as to other classes. Data were collected using surveys, interviews and classroom observations, and analyzed using qualitative methods. The data show that while most students were able …

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Choline Chloride Eutectics: Low Temperature Applications, Kaila M. Kuehn, Camille M. Massmann, Natalie R. Sovell Jan 2017

Choline Chloride Eutectics: Low Temperature Applications, Kaila M. Kuehn, Camille M. Massmann, Natalie R. Sovell

The Journal of Undergraduate Research

Deep eutectic solvents (DESs) have a lower melting point than each of their individual components due to ion dipole interactions or hydrogen bonding. Traditionally, DES are used for processing metals through plating and have many synthesis applications. DES are able to be substituted for hazardous solvents that are traditionally used for metal plating and synthesis. This, along with many other advantageous properties, appear promising for the use of DESs as solvents or for use in electrochemical systems, particularly at low temperatures. Choline chloride:propylene glycol was a novel DES synthesized and analyzed for its properties, including melting point, viscosity, conductivity, heat …

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Investigating The Atmospheric Production Of Perchlorate: Inference From Polar Ice Cores, Thomas S. Cox Jan 2017

Investigating The Atmospheric Production Of Perchlorate: Inference From Polar Ice Cores, Thomas S. Cox

Electronic Theses and Dissertations

Perchlorate (ClO4) in the environment is of concern, because of potential health risks to humans, among other reasons. Evidence suggests that the majority of environmental perchlorate is formed in the atmosphere (likely in the stratosphere), in chemical processes involving ozone and stratospheric chlorine. A lack of knowledge in regards to the processes has resulted in a limited understanding of the environmental conditions and variables that influence perchlorate production and consequently perchlorate prevalence and variability in the environment. In this study, perchlorate was measured, using an established ion chromatography-­‐electrospray ionization-­‐tandem mass spectrometry (IC-­‐ESI-­‐ MS/MS) technique, in over 1,600 snowpit …

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Relationship Of The Fractal And Chemical Characteristics Of Self-Assembled Natural Organic Matter, Dennis K. Gibson Jan 2017

Relationship Of The Fractal And Chemical Characteristics Of Self-Assembled Natural Organic Matter, Dennis K. Gibson

Electronic Theses and Dissertations

Natural Organic Matter (NOM) is a heterogeneous mixture formed by the degradation of organic substances during early diagenesis in surficial environments. It has been shown that the interaction of the components that comprise this mixture has a significant impact on its microbial mineralization to CO2. The extent of NOM selfassembly is emerging as an important factor in understanding its role in the global geochemical carbon cycle, and it is beginning to appear that it may be more important than the chemical composition of a sample. The overall goal of this research is to establish NOM’s self-assembled “architecture” and …

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Self-Assembled Architecture Of Natural Organic Matter, Cynthia Johnson-Edler Jan 2017

Self-Assembled Architecture Of Natural Organic Matter, Cynthia Johnson-Edler

Electronic Theses and Dissertations

This investigation focuses on the determination of the architecture of the natural organic matter (NOM) contained within a soft coal-like material, an agricultural soil and a peat material. NOM has been extracted from bulk materials, fractionated, reassembled, then characterized by 13C Solid State NMR, Pulsed-Field Gradient NMR (PFG-NMR), and Small Angle Neutron Scattering (SANS). Interpretation of the data obtained by SANS has established that the majority of the components of NOM are mass fractals in solution and surface fractals in the solid state. Surface-to-volume ratios calculated with PFGNMR data indicate the NOM components studied have varying disk-like shapes. These …

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Deep Eutectic Solvents Synthesis, Characterization And Applications In Pretreatment Of Lignocellulosic Biomass, Ganesh Degam Jan 2017

Deep Eutectic Solvents Synthesis, Characterization And Applications In Pretreatment Of Lignocellulosic Biomass, Ganesh Degam

Electronic Theses and Dissertations

There has been an increased interest in green solvents and biofuels with the growing environmental awareness across the globe. Conventional methods of biofuel production involve the use of large quantities of molecular solvents and ionic liquids (ILs), but they have the drawbacks of high vapor pressure (organic solvents), toxicity, and recyclability in terms of a sustainability point of view. Deep eutectic solvents (DESs) have recently emerged as green alternatives to molecular solvents and ionic liquids (ILs). They are defined as eutectic mixtures formed between quaternary ammonium, phosphonium or sulfonium salts and hydrogen bond donors (HBDs) with the freezing temperature lower …

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Comprehensive Structural, Thermal And Toxicological Characterization Of 1-Ethyl-3-Methylimidazolium Alkylbenzenesulfonate Ionic Liquids, Hiranmayee Kandala Jan 2017

Comprehensive Structural, Thermal And Toxicological Characterization Of 1-Ethyl-3-Methylimidazolium Alkylbenzenesulfonate Ionic Liquids, Hiranmayee Kandala

Electronic Theses and Dissertations

Synthesis and characterization of 1-ethyl-3- methylimidazolium alkylbenzenesulfonate ionic liquids for extraction of lignin from prairie cord grass have been studied. The ionic liquids (ILs) 1-ethyl-3- methylimidazolium benzenesulfonate (EBS), 1-ethyl-3- methylimidazolium toluenesulfonate (ETS) and 1-ethyl-3- methylimidazolium xylenesulfonate (EXS) have been synthesized in this research. An extensive structural, physical, thermal and toxicological characterization has been performed to understand the behavior of these ionic liquids. The reaction yield for the synthesis of EBS, ETS, and EXS ionic liquids was determined to be 91.2 ± 1.5 %, 96.1 ± 0.7 %, 99.0 ± 0.5 % respectively. Spectral analysis using NMR and FTIR confirms the …

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Cbl And Cbl-B Dictate Csf-1r Endocytic Traffic And Signaling In Macrophages, Lu Huang Jan 2017

Cbl And Cbl-B Dictate Csf-1r Endocytic Traffic And Signaling In Macrophages, Lu Huang

Electronic Theses and Dissertations

Macrophage colony stimulating factor receptor (CSF-1R or MCSFR) is a receptor tyrosine kinase essential for the growth and function of macrophages. Understanding the mechanisms that regulate CSF-1R activation and deactivation will provide insights to clinical treatment of macrophage related diseases including chronic inflammation and cancer. Previously, our laboratory showed that CSF-1R undergoes a novel membrane trafficking route that involves macropinocytosis to deactivate CSF-1R signaling. This thesis makes the discovery that the ubiquitin ligases Cbl and Cbl-b cooperate to regulate CSF-1R endocytosis and traffic to macropinosome in macrophages. Macrophages were derived from mice knocked out for Cbl, Cbl-b or the double …

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