Open Access. Powered by Scholars. Published by Universities.®

Chemistry Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 12 of 12

Full-Text Articles in Chemistry

Highly Efficient Dopamine Sensing With A Carbon Nanotube-Encapsulated Metal Chalcogenide Nanostructure, Harish Singh, Jiandong Wu, Kurt A.L. Lagemann, Manashi Nath Mar 2024

Highly Efficient Dopamine Sensing With A Carbon Nanotube-Encapsulated Metal Chalcogenide Nanostructure, Harish Singh, Jiandong Wu, Kurt A.L. Lagemann, Manashi Nath

Chemical and Biochemical Engineering Faculty Research & Creative Works

Carbon nanotube-encapsulated nickel selenide composite nanostructures were used as nonenzymatic electrochemical sensors for dopamine detection. These composite nanostructures were synthesized through a simple, one-step, and environmentally friendly chemical vapor deposition method, wherein the CNTs were formed in situ from pyrolysis of a carbon-rich metallo-organic precursor. The composition and morphology of these hybrid NiSe2-filled carbon nanostructures were confirmed by powder X-ray diffraction, Raman, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy images. Electrochemical tests demonstrated that the as-synthesized hybrid nanostructures exhibited outstanding electrocatalytic performance toward dopamine oxidation, with a high sensitivity of 19.62 μA μM-1 cm-2, low detection limit, broad linear …


Repeated Low-Level Blast Exposure Alters Urinary And Serum Metabolites, Austin Sigler, Jiandong Wu, Annalise Pfaff, Olajide Adetunji, Paul Ki-Souk Nam, Donald James, Casey Burton, Honglan Shi May 2023

Repeated Low-Level Blast Exposure Alters Urinary And Serum Metabolites, Austin Sigler, Jiandong Wu, Annalise Pfaff, Olajide Adetunji, Paul Ki-Souk Nam, Donald James, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Repeated exposure to low-level blast overpressures can produce biological changes and clinical sequelae that resemble mild traumatic brain injury (TBI). While recent efforts have revealed several protein biomarkers for axonal injury during repetitive blast exposure, this study aims to explore potential small molecule biomarkers of brain injury during repeated blast exposure. This study evaluated a panel of ten small molecule metabolites involved in neurotransmission, oxidative stress, and energy metabolism in the urine and serum of military personnel (n = 27) conducting breacher training with repeated exposure to low-level blasts. The metabolites were analyzed using HPLC—tandem mass spectrometry, and the Wilcoxon …


Transport And Plugging Performance Evaluation Of A Novel Re-Crosslinkable Microgel Used For Conformance Control In Mature Oilfields With Super-Permeable Channels, Adel Alotibi, T. Song, Baojun Bai, Thomas P. Schuman Jan 2023

Transport And Plugging Performance Evaluation Of A Novel Re-Crosslinkable Microgel Used For Conformance Control In Mature Oilfields With Super-Permeable Channels, Adel Alotibi, T. Song, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Preformed particle gels (PPG) have been widely applied in oilfields to control excessive water production. However, PPG has limited success in treating opening features because the particles can be flushed readily during post-water flooding. We have developed a novel micro-sized Re-crosslinkable PPG (micro-RPPG) to solve the problem. The microgel can re-crosslink to form a bulk gel, avoiding being washed out easily. This paper evaluates the novel microgels' transport and plugging performance through super-permeable channels. Micro-RPPG was synthesized and evaluated for this study. Its storage moduli after fully swelling are approximately 82 Pa. The microgel characterization, self-healing process, transportation behavior, and …


Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi May 2022

Establishing Pteridine Metabolism In A Progressive Isogenic Breast Cancer Cell Model – Part Ii, Lindsey Rasmussen, Zachary Foulks, Jiandong Wu, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Introduction: Determining the biological significance of pteridines in cancer development and progression remains an important step in understanding the altered levels of urinary pteridines seen in certain cancers. Our companion study revealed that several folate-derived pteridines and lumazines correlated with tumorigenicity in an isogenic, progressive breast cancer cell model, providing direct evidence for the tumorigenic origin of pteridines. Objectives: This study sought to elucidate the pteridine biosynthetic pathway in a progressive breast cancer model via direct pteridine dosing to determine how pteridine metabolism changes with tumorigenicity. Methods: First, MCF10AT breast cancer cells were dosed individually with 15 pteridines to determine …


Plasma Polymerization Of Tetrafluoroethylene. Iii. Capacitive Audio Frequency (10 Khz) And Ac Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley Jan 1979

Plasma Polymerization Of Tetrafluoroethylene. Iii. Capacitive Audio Frequency (10 Khz) And Ac Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley

Chemical and Biochemical Engineering Faculty Research & Creative Works

The plasma polymerization of tetrafluoroethylene (TFE) is studied in a capacitively coupled system with internal electrodes using a 10 kHz (af) and a 60 Hz (ac) source. The emphasis is on identifying conditions that are compatible with continuous coating of plasma polymer on a substrate moving through the center of the interelectrode gap. Operation at a pressure below 100 mTorr is most favorable for deposition of a substantial portion of the plasma polymer on this substrate. Plasma polymer deposited in this way is characterized by ESCA and by deposition rate data and compared to that deposited using rf power in …


Plasma Polymerization Of Tetrafluoroethylene. Ii. Capacitive Radio Frequency Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley Jan 1979

Plasma Polymerization Of Tetrafluoroethylene. Ii. Capacitive Radio Frequency Discharge, N. (Nicholas) C. Morosoff, H. Yasuda, E. S. Brandt, C. N. Reilley

Chemical and Biochemical Engineering Faculty Research & Creative Works

The plasma polymerization of tetrafluoroethylene (TFE) is studied in a capacitively coupled system with internal electrodes using radio frequency (13.56 MHz) power. The emphasis is on identifying conditions that are compatible with continuous coating of plasma polymer on a substrate moving through the center of the interelectrode gap. At high pressure (500 mTorr), deposition of plasma polymer is primarily on the electrodes rather than on a substrate placed midway between electrodes. Glow is observed in only part of the interelectrode gap at low powers and fills the gap only at high power levels. The use of a magnetic field effects …


Plasma Polymerization Of Tetrafluoroethylene. I. Inductive Radio Frequency Discharge, H. Yasuda, N. Morosoff, E. S. Brandt, C. N. Reilley Jan 1979

Plasma Polymerization Of Tetrafluoroethylene. I. Inductive Radio Frequency Discharge, H. Yasuda, N. Morosoff, E. S. Brandt, C. N. Reilley

Chemistry Faculty Research & Creative Works

The plasma polymerization of tetrafluoroethylene in an inductively coupled radio frequency glow discharge, using a flow system, was studied. A simple long tube reactor, with the coupling coil placed at the middle of the tube and gas entrance and exit at the respective ends, was used. Deposition rates and the chemical nature of the polymer (as revealed by ESCA spectra and surface energy studies) are obtained as a function of location in the reactor tube with respect to the coupling coil and of applied energy per unit mass of tetrafluoroethylene (W/FM). It was found that a fluorine poor polymer, containing …


Film Formation On Anodically Polarized Lead, H. Vaidyanathan, Ram A. Narasagoudar, Thomas J. O'Keefe, William Joseph James, James W. Johnson Jan 1974

Film Formation On Anodically Polarized Lead, H. Vaidyanathan, Ram A. Narasagoudar, Thomas J. O'Keefe, William Joseph James, James W. Johnson

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.


The Anodic Dissolution Of Cadmium, James W. Johnson, E. Deng, S. C. Lai, William Joseph James Jan 1967

The Anodic Dissolution Of Cadmium, James W. Johnson, E. Deng, S. C. Lai, William Joseph James

Chemical and Biochemical Engineering Faculty Research & Creative Works

The anodic dissolution of cadmium has been studied in aqueous solutions containing Cl−, Br−, I−, Ac−, SO4=, and NO3− ions. The normal valence (+2) was found in all solutions with the exception of NO3−. The apparent valence (calculated) of cadmium ions in nitrate solutions varied from 1.2 to 2.0 and was found to be a function of NO3− concentration, current density, and temperature. An anodic dissolution mechanism has been proposed involving local corrosion and disintegration of the anode which is consistent with the experimental results. © 1967, The Electrochemical Society, Inc. All rights reserved.


Radial Pressure Gradient In Turbulent Pipe Flow, Gary Kent Patterson, Walter J. Ewbank, Virgil A. Sandborn Jan 1967

Radial Pressure Gradient In Turbulent Pipe Flow, Gary Kent Patterson, Walter J. Ewbank, Virgil A. Sandborn

Chemical and Biochemical Engineering Faculty Research & Creative Works

Measurements made with a Prandtl static pressure probe have demonstrated that a radial pressure gradient does exist in turbulent pipe flow with approximately the magnitude predicted by Sandborn from hot-wire anemometry measurements.


The Mechanism Of The Electrooxidation Of Acetylene On Gold, James W. Johnson, J. L. Reed, William Joseph James Jan 1967

The Mechanism Of The Electrooxidation Of Acetylene On Gold, James W. Johnson, J. L. Reed, William Joseph James

Chemical and Biochemical Engineering Faculty Research & Creative Works

Acetylene has been oxidized anodically in aqueous solutions at 80 °C on gold electrodes. It was found that the partial oxidation to CO2 was accompanied by a polymer formation. Effects of potential, acetylene partial pressure, pH, and temperature on the rate (current) were measured. A discontinuity in the Tafel curves was noted that indicated a change in the reaction mechanism with potential. The discontinuity was also pH dependent. A mechanism involving the discharge of H2O and/or OH− has been proposed that is consistent with the experimental results. © 1967, The Electrochemical Society, Inc. All rights reserved.


The Effect Of Concentration On The Viscosities Of Solutions Of Linear Flexible High Polymers, Lung Yu Chou, Jacques L. Zakin Jan 1967

The Effect Of Concentration On The Viscosities Of Solutions Of Linear Flexible High Polymers, Lung Yu Chou, Jacques L. Zakin

Chemical and Biochemical Engineering Faculty Research & Creative Works

Viscosity-concentration results in the moderately concentrated range for four samples of polyisobutylene (molecular weights of 1.3 x 104 to 1.0 x 106) in cyclohexane (concentrations up to 4.7 g./dl.) and in benzene (concentrations up to 7.0 g./dl.) at 24°C. (a theta solvent) showed molecular weight and goodness of solvent dependencies similar to those reported earlier for three other polymers. For polyisobutylene, polystyrene, and a copolymer of styrene and methyl methaerylate in good solvents, viscosity-concentration data plotted as ηsp. C[η] vs. k′[η]C fit a single curve. The linear region of this curve suggests that the Huggins equation is useful to C[η] …