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12,596 full-text articles. Page 1 of 247.

Science History On The Road: An Overview, Mary Orna 2016 College of New Rochelle

Science History On The Road: An Overview, Mary Orna

Mary Virgina Orna

No abstract provided.


Historic Mineral Pigments: Colorful Benchmarks Of Ancient Civilizations, Mary Orna 2016 College of New Rochelle

Historic Mineral Pigments: Colorful Benchmarks Of Ancient Civilizations, Mary Orna

Mary Virgina Orna

No abstract provided.


New Directions In Archaeological Chemistry, Mary Orna 2016 College of New Rochelle

New Directions In Archaeological Chemistry, Mary Orna

Mary Virgina Orna

No abstract provided.


Copper-Based Synthetic Medieval Blue Pigments, Mary Orna 2016 College of New Rochelle

Copper-Based Synthetic Medieval Blue Pigments, Mary Orna

Mary Virgina Orna

No abstract provided.


Cours Enzymologie Fondamentale Et Appliquée (Niveau Master 1), Mamoudou H. DICKO, Prof. 2016

Cours Enzymologie Fondamentale Et Appliquée (Niveau Master 1), Mamoudou H. Dicko, Prof.

Pr. Mamoudou H. DICKO, PhD

L'objectif principal de ce cours est de rappeler et donner aux étudiants les connaissances indispensables en enzymologie appliquée, à savoir :
- connaître la structure des enzymes, les méthodes d’extraction, de purification, de dosage et de caractérisation (électrophorèse, zymographie, etc.) des enzymes ;
- comprendre les principes fondamentaux de la cinétique chimique et la cinétique enzymatique y compris le rôle des inhibiteurs et autres effecteurs;
- comprendre les méthodes d’immobilisation des enzymes et leurs conséquences positives ou négatives dans la biocatalyse enzymatique;
- comprendre les différends domaines d’utilisation des enzymes en biochimie analytique, bio-industries, industrie agro-alimentaires, analyses bio-médicales, en diagnostic, etc.


Preface To Electrochemistry, Past And Present, Mary Orna 2016 College of New Rochelle

Preface To Electrochemistry, Past And Present, Mary Orna

Mary Virgina Orna

No abstract provided.


Oxygen Electrode, Mary Orna 2016 College of New Rochelle

Oxygen Electrode, Mary Orna

Mary Virgina Orna

No abstract provided.


Ultrafast Spectroscopy And Energy Transfer In An Organic/Inorganic Composite Of Zinc Oxide And Graphite Oxide, Jeff A. Secor 2016 Graduate Center, City University of New York

Ultrafast Spectroscopy And Energy Transfer In An Organic/Inorganic Composite Of Zinc Oxide And Graphite Oxide, Jeff A. Secor

All Dissertations, Theses, and Capstone Projects (2014-Present)

The energy transfers and nature of defect levels of an organic/inorganic composite of Zinc Oxide and Graphite are studied with multidimensional spectroscopy. The edge and surface states of each composite are uncovered using excitation emission experiments showing which defect states are mediating the energy transfer from the metal oxide to the graphite oxide. Multidimensional time resolved spectroscopy further describes the effect of the carbon phase on the energy transfer pathways in the material.


Random Number Simulations Reveal How Random Noise Affects The Measurements And Graphical Portrayals Of Self-Assessed Competency, Edward Nuhfer, Christopher Cogan, Steven Fleisher, Eric Gaze, Karl Wirth 2016 California State University (retired)

Random Number Simulations Reveal How Random Noise Affects The Measurements And Graphical Portrayals Of Self-Assessed Competency, Edward Nuhfer, Christopher Cogan, Steven Fleisher, Eric Gaze, Karl Wirth

Numeracy

Self-assessment measures of competency are blends of an authentic self-assessment signal that researchers seek to measure and random disorder or "noise" that accompanies that signal. In this study, we use random number simulations to explore how random noise affects critical aspects of self-assessment investigations: reliability, correlation, critical sample size, and the graphical representations of self-assessment data. We show that graphical conventions common in the self-assessment literature introduce artifacts that invite misinterpretation. Troublesome conventions include: (y minus x) vs. (x) scatterplots; (y minus x) vs. (x) column graphs aggregated as quantiles; line charts that display data aggregated as quantiles; and ...


Tio2/Biox (X = Cl, Br, I) Hybrid Microspheres For Artificial Waste Water And Real Sample Treatment Under Visible Light Irradiation, Mohammad Mansoob Khan, Dr, Dr Youngku Sohn 2016

Tio2/Biox (X = Cl, Br, I) Hybrid Microspheres For Artificial Waste Water And Real Sample Treatment Under Visible Light Irradiation, Mohammad Mansoob Khan, Dr, Dr Youngku Sohn

Dr. Mohammad Mansoob Khan

The hybridization of two different materials is important for achieving improved photocatalytic degradation properties. Generally, photocatalysts do not show good linear catalytic performance toward all the dyes. This paper reports the synthesis of nano-assembled TiO2/BiOX (X = Cl, Br, or I) hybrid microspheres, which were confirmed by powder X-ray diffraction, field emission scanning electron microscopy, electron transmission microscopy, UV–visible spectroscopy, Fourier-transform infrared spectroscopy, and photoluminescence spectroscopy. The synthesized photocatalysts were examined extensively for their photocatalytic activities with single (orange G and tartrazine), mixed dyes (methyl orange + rhodamine B + methylene blue), natural dyes extracted from grapes and cabbages (real ...


Molecular Interpretation Of A Trigger For Controlling An Amine Isocyanate Polyurethane Reaction, Katherine V. Carrasquillo 2016 PSE graduate student

Molecular Interpretation Of A Trigger For Controlling An Amine Isocyanate Polyurethane Reaction, Katherine V. Carrasquillo

Masters Theses May 2014 - current

The temperature profile needed to complete the reaction between the sodium-diamine complex and the isocyanate terminated prepolymer has been established. The sodium diamine complex has the advantage of blocking the nearly instantaneous reaction between the diamine and isocyanate from taking place until it is released at elevated temperatures. Because of its low melting temperature (~40 °C) and its low molecular weight (low viscosity), this chain extension reaction is not dependent on the participation of the prepolymer. Instead, the rate of reaction is dependent on the dissolution of the 4,4’-methylenedianiline (MDA) complex into the system. The dissolution of the ...


Operation Of An Inexpensive Bipolar Alkaline Electrolyser Producing A Mix Of H2/O2 Fuel, Cian O'reilly, michael Farrell, David Harvey, John Cassidy 2016 Dublin Institute of Technology

Operation Of An Inexpensive Bipolar Alkaline Electrolyser Producing A Mix Of H2/O2 Fuel, Cian O'Reilly, Michael Farrell, David Harvey, John Cassidy

Articles

This paper describes the operation of a bipolar alkaline electrolyser which is at least 60% efficient at evolving a hydrogen/oxygen mix. The electrolyser consists of 12 stainless steel ( SS316L) electrodes of area 5400 cm2 in a sealed polypropylene unit. A pulsed potential waveform is applied to the electrodes in 0.12M KOH electrolyte yielding on the order of 320 dm3/kWh of the hydrogen /oxygen mix. This compares favourably with commercial devices that are designed to yield hydrogen alone.


The Origin Of Amino Acids In Lunar Regolith Samples, Jamie E. Elsila, Michael P. Callahan, Jason P. Dworkin, Daniel P. Glavin, Hannah L. McLain, Sarah K. Noble, Everett K. Gibson Jr. 2016 NASA Goddard Space Flight Center

The Origin Of Amino Acids In Lunar Regolith Samples, Jamie E. Elsila, Michael P. Callahan, Jason P. Dworkin, Daniel P. Glavin, Hannah L. Mclain, Sarah K. Noble, Everett K. Gibson Jr.

Chemistry Faculty Publications and Presentations

We analyzed the amino acid content of seven lunar regolith samples returned by the Apollo 16 and Apollo 17 missions and stored under NASA curation since collection using ultrahigh-performance liquid chromatography with fluorescence detection and time-of-flight mass spectrometry. Consistent with results from initial analyses shortly after collection in the 1970s, we observed amino acids at low concentrations in all of the curated samples, ranging from 0.2 parts-per-billion (ppb) to 42.7 ppb in hot-water extracts and 14.5–651.1 ppb in 6 M HCl acid-vapor-hydrolyzed, hot-water extracts. Amino acids identified in the Apollo soil extracts include glycine, D- ...


Physical And Electrochemical Area Determination Of Electrodeposited Ni, Co, And Nico Thin Films, Matthew Gira, Kevin Tkacz, Jennifer R. Hampton 2016 Hope College

Physical And Electrochemical Area Determination Of Electrodeposited Ni, Co, And Nico Thin Films, Matthew Gira, Kevin Tkacz, Jennifer R. Hampton

Faculty Publications

The surface area of electrodeposited thin films of Ni, Co, and NiCo was evaluated using electrochemical double-layer capacitance, electrochemical area measurements using the [Ru(NH3)6]3+/[Ru(NH3)6]2+ redox couple, and topographic atomic force microscopy (AFM) imaging. These three methods were compared to each other for each composition separately and for the entire set of samples regardless of composition. Double-layer capacitance measurements were found to be positively correlated to the roughness factors determined by AFM topography. Electrochemical area measurements were found to be less correlated with measured roughness factors as well as applicable only to ...


Sign Learning Kink-Based (Silk) Quantum Monte Carlo For Molecular Systems, Xiaoyao Ma, Randall W. Hall, Frank Löffler, Karol Kowalski, Kiran Bhaskaran-Nair, Mark Jarrell, Juana Moreno 2016 Department of Physics and Astronomy, Louisiana State University, Baton Rouge

Sign Learning Kink-Based (Silk) Quantum Monte Carlo For Molecular Systems, Xiaoyao Ma, Randall W. Hall, Frank Löffler, Karol Kowalski, Kiran Bhaskaran-Nair, Mark Jarrell, Juana Moreno

Collected Faculty Scholarship

The Sign Learning Kink (SiLK) based Quantum Monte Carlo (QMC) method is used to calculate the ab initioground state energies for multiple geometries of the H2O, N2, and F2 molecules. The method is based on Feynman’s path integral formulation of quantum mechanics and has two stages. The first stage is called the learning stage and reduces the well-known QMC minus sign problem by optimizing the linear combinations of Slater determinants which are used in the second stage, a conventional QMC simulation. The method is tested using different vector spaces and compared to the results of ...


Seasonal Evolution Of Active Layer Formation In Subarctic Peat Plateaux And Implications For Dissolved Organic Matter Composition And Transfer, Jennifer L. Hickman 2016 Wilfrid Laurier University

Seasonal Evolution Of Active Layer Formation In Subarctic Peat Plateaux And Implications For Dissolved Organic Matter Composition And Transfer, Jennifer L. Hickman

Theses and Dissertations (Comprehensive)

Peat-accumulating wetlands are ecosystems whose rate of photosynthetic production of organic matter is greater than that of its decomposition, resulting in a build up of soil organic matter that may take centuries to fully decompose. Carbon (C) stocks within these ecosystems are a function of inputs from photosynthesis, and losses from heterotrophic decomposition. Due to the short growing season and overall cold climate of boreal and tundra regions, C has been accumulating within these landscapes, mostly in soil organic matter, since the last glaciation. Climate change, predicted to result in rising temperatures and increased precipitation, has begun to degrade the ...


Investigating Freezing Point Depression And Cirrus Cloud Nucleation Mechanisms Using A Differential Scanning Calorimeter, Kentaro Y. Bodzewski, Ryan L. Caylor, Ashley M. Comstock, Austin T. Hadley, Felisha M. Imholt, Kory D. Kirwan, Kira S. Oyama, Matthew E. Wise 2015

Investigating Freezing Point Depression And Cirrus Cloud Nucleation Mechanisms Using A Differential Scanning Calorimeter, Kentaro Y. Bodzewski, Ryan L. Caylor, Ashley M. Comstock, Austin T. Hadley, Felisha M. Imholt, Kory D. Kirwan, Kira S. Oyama, Matthew E. Wise

Matthew E. Wise

A differential scanning calorimeter was used to study homogeneous nucleation of ice from micron-sized aqueous ammonium sulfate aerosol particles. It is important to understand the conditions at which these particles nucleate ice because of their connection to cirrus cloud formation. Additionally, the concept of freezing point depression, a topic commonly encountered in undergraduate science courses, was experimentally studied using an instrumental technique. As expected, when the concentration of ammonium sulfate in the particles increased, their freezing and melting temperatures decreased. The data was consistent with previous work that showed water activity is the determinant for homogeneous ice nucleation ...


Fluorescein Tri-Aldehyde Promotes The Selective Detection Of Homocysteine, Aabha Barve, Mark Lowry, Jorge O. Escobedo, Josephrajan Thainashmuthu, Robert M. Strongin 2015 Portland State University

Fluorescein Tri-Aldehyde Promotes The Selective Detection Of Homocysteine, Aabha Barve, Mark Lowry, Jorge O. Escobedo, Josephrajan Thainashmuthu, Robert M. Strongin

Robert M. Strongin

Elevated homocysteine levels are a well-known independent risk factor for cardiovascular disease. To date, relatively few selective fluorescent probes for homocysteine detection have been reported. The lack of sensing reagents and remaining challenges largely derive from issues of sensitivity and/or selectivity. For example, homocysteine is a structural homologue of the more abundant (ca, 20-25 fold) aminothiol cysteine, differing only by an additional methylene group side chain. Fluorescein tri-aldehyde, described herein, has been designed and synthesized as a sensitive and selective fluorophore for the detection of homocysteine in human plasma samples. It responds to analytes selectively via a photoinduced electron ...


Exploring Alternative Cobalt Redox Mediators And Β-Diketonate Non-Innocent Ligands For Applications In Dye-Sensitized Solar Cells, Nicholas Anthony Lee 2015 University of Massachusetts Boston

Exploring Alternative Cobalt Redox Mediators And Β-Diketonate Non-Innocent Ligands For Applications In Dye-Sensitized Solar Cells, Nicholas Anthony Lee

Graduate Masters Theses

Dye-sensitized solar cells (DSSCs) have seen an influx of research since Grätzel’s seminal 1991 Nature paper. Although easier to fabricate and cheaper to produce, their commercial viability depends on reaching power conversion efficiencies on par with current photovoltaic technologies such as silicon thin film solar cells. This thesis contributes to the growing library of new redox mediators and light-absorbing photosensitizers as pathways to improved DSSC performance. Following a thorough review of DSSC technologies and advancements in Chapter 1, Chapter 2 introduces a novel cobalt(III/II) redox mediator, [Co(bpq)2]3+/2+ (bpq = 2,6-bis(8-quinolinyl)pyridine) and ...


Photooxidation Reactions Of Small-Chain Methyl Esters, Aerosol Photoelectron Spectroscopy, And The Photodissociation Of Ethylenediamine, Giel Muller 2015 University of San Francisco

Photooxidation Reactions Of Small-Chain Methyl Esters, Aerosol Photoelectron Spectroscopy, And The Photodissociation Of Ethylenediamine, Giel Muller

Master's Theses

Research conducted at the University of San Francisco is presented within this masters thesis, including the Cl-initiated photooxidation reactions of methyl propanoate, methyl butanoate, and methyl valerate (pentanoate), the aerosol photoelectron spectroscopy of isoprene and gamma-valerolactone, and the TPEPICO investigation of ethylenediamine. Experiments were conducted at the Lawrence Berkeley National Lab Advanced Light Source (ALS), the National Synchrotron Radiation Research Center in Hsinchu City (NSRRC), and the University of Stockton in California, respectively.


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