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Applying Density Functional Theory Simulations To Study The Charge Balancing And Structure Directing Roles Of Fluoride In Zeolite Synthesis, Tongkun Wang Nov 2023

Applying Density Functional Theory Simulations To Study The Charge Balancing And Structure Directing Roles Of Fluoride In Zeolite Synthesis, Tongkun Wang

Doctoral Dissertations

Zeolites represent a major cornerstone of today’s energy industry as the most-used petrochemical catalyst by weight in the world. Constituted by tetrahedra of T-atoms including Si, Al, Ge and Ti, zeolites form a huge family of nano-porous crystalline materials which also provide reliable candidates for novel, energy related applications such as efficient separations, hydrogen-purifying/storing and conversions from biomass to biofuel. However, the formation mechanism of zeolite is still not clear, as synthesis processes are complicated by requirements including structure directing agents (SDAs), hydroxide or fluoride medium, and experimental conditions like temperature. Attempts for designing new zeolite structures still fall in …


Defoliation Severity Is Positively Related To Soil Solution Nitrogen Availability And Negatively Related To Soil Nitrogen Concentrations Following A Multi-Year Invasive Insect Irruption, Emma Conrad-Rooney, Audrey Barker Plotkin, Valerie J. Pasquarella, Joseph Elkinton, Jennifer L. Chandler, Jaclyn Hatala Matthes Jan 2020

Defoliation Severity Is Positively Related To Soil Solution Nitrogen Availability And Negatively Related To Soil Nitrogen Concentrations Following A Multi-Year Invasive Insect Irruption, Emma Conrad-Rooney, Audrey Barker Plotkin, Valerie J. Pasquarella, Joseph Elkinton, Jennifer L. Chandler, Jaclyn Hatala Matthes

Environmental Conservation Faculty Publication Series

Understanding connections between ecosystem nitrogen (N) cycling and invasive insect defoliation could facilitate the prediction of disturbance impacts across a range of spatial scales. In this study we investigated relationships between ecosystem N cycling and tree defoliation during a recent 2015–18 irruption of invasive gypsy moth caterpillars (Lymantria dispar), which can cause tree stress and sometimes mortality following multiple years of defoliation. Nitrogen is a critical nutrient that limits the growth of caterpillars and plants in temperate forests. In this study, we assessed the associations among N concentrations, soil solution N availability and defoliation intensity by L. dispar …


Characterization Of Highly Heterogeneous Heparin-Protein Complexes Using Novel Mass Spectrometry-Based Approaches, Yunlong Zhao Nov 2017

Characterization Of Highly Heterogeneous Heparin-Protein Complexes Using Novel Mass Spectrometry-Based Approaches, Yunlong Zhao

Doctoral Dissertations

Heparin-like glycosaminoglycan (GAG) is a family of polysaccharide involved in variety of physiological processes. They have potentials to interact with a broad range of proteins and many of them hold crucial values in regulation of protein functions. My dissertation addresses the significance and challenges in the field of heparin-mediated studies, with a focus on the questions in biological and analytical aspects, which are largely hindered by the structural heterogeneity and function diversity of heparin. My dissertation reports the efforts I made in the past few years with respect to the development of novel analytical strategies based on a combination of …


Nanoparticle As Supramolecular Platform For Delivery And Bioorthogonal Catalysis, Gulen Yesilbag Tonga Nov 2017

Nanoparticle As Supramolecular Platform For Delivery And Bioorthogonal Catalysis, Gulen Yesilbag Tonga

Doctoral Dissertations

Nanoparticles (NPs) are being investigated widely for many applications including imaging, drug delivery, therapeutics, materials, and catalysis due to their unique and tunable physical and chemical properties. Among NPs, gold nanoparticles (AuNPs) have attracted great attention due to ease of synthesis and surface functionalization, inertness of the core, biocompatibility, and functional versatility. Introducing supramolecular chemistry into the nanoparticle-based platforms brings out controllable properties, dynamic self assembly processes, and adjustable performance. My research has focused on the synthesis of AuNPs bearing different surface functionalities and their host-guest interactions with synthetic small molecules or commercially available hydrophobic catalysts for delivery and therapeutic …


Studying Nanoparticle/Cell And Nanoparticle/Biosurface Interaction With Mass Spectrometry, Singyuk Hou Nov 2015

Studying Nanoparticle/Cell And Nanoparticle/Biosurface Interaction With Mass Spectrometry, Singyuk Hou

Masters Theses

Nanoparticles (NPs) have been used widely in various fields ranging from biomedical applications to life science due to their highly tunable properties. It is essential to understanding how NPs interact with biological systems of interest, therefore, analytical platforms to efficiently track NPs from cell to animal level are essential. In this thesis, laser desorption ionization mass spectrometry (LDI-MS) and inductively-coupled plasma mass spectrometry (ICP-MS) has been developed and applied to quantify NP/cell and NP/biological surface interactions. These two methods provide fast, label-free and quantitative analysis. New capability of LDI-MS to differentiate cell surface-bound and internalized NPs were established and ICP-MS …


Studies In The Atomic Spectrometric Determination And Speciation Of Arsenic In Environmental Samples, Nan Wang Aug 2014

Studies In The Atomic Spectrometric Determination And Speciation Of Arsenic In Environmental Samples, Nan Wang

Doctoral Dissertations

The application of work described in this dissertation, the determination of total and arsenic species in water and rice samples, is of considerable societal importance as large numbers of the citizens of many countries around the world are exposed to potentially harmful concentrations of these carcinogenic compounds by daily consumption. The field of analytical chemistry is crucial to support the operation of any treatment to decrease arsenic concentrations as well as any regulations and legislation regarding arsenic in food and the environment. The current goals of research in trace arsenic measurements and speciation are to increase knowledge of the subject …


Professor Zbigniew Jaworowski – In Memoriam, Ludwik Dobrzyn´Ski, Michael P.R. Waligórski, Marek K. Janiak Dec 2012

Professor Zbigniew Jaworowski – In Memoriam, Ludwik Dobrzyn´Ski, Michael P.R. Waligórski, Marek K. Janiak

Dose-Response: An International Journal

No abstract provided.


Evaluating The Influence Of Disturbance And Climate On Red Spruce (Picea Rubens Sarg.) Community Dynamics At Its Southern Range Margin, Relena R. Ribbons Jan 2011

Evaluating The Influence Of Disturbance And Climate On Red Spruce (Picea Rubens Sarg.) Community Dynamics At Its Southern Range Margin, Relena R. Ribbons

Masters Theses 1911 - February 2014

Picea rubens(red spruce) populations experienced a synchronous rangewide decline in growth and vigor starting in the 1960’s, which was likely caused by climate change or environmental disturbances (e.g., acid deposition); However, it is yet unknown if populations continue to decline or have recovered. In the context of global warming, red spruce is a species of concern because it is at its southern continuous range margin in Massachusetts. This study uses tree-ring data coupled with population data from permanent plots to quantify the status of red spruce in Massachusetts. Tree cores were extracted from red spruce and used to examine …


Synthesis Of Transportation Fuels From Biomass:  Chemistry, Catalysts, And Engineering, George W. Huber, S. Iborra, A. Corma Jan 2006

Synthesis Of Transportation Fuels From Biomass:  Chemistry, Catalysts, And Engineering, George W. Huber, S. Iborra, A. Corma

George W. Huber

No abstract provided.


Phosphorus Management In Cranberry Systems, Joan Davenport, Carolyn Demoranville Jan 1996

Phosphorus Management In Cranberry Systems, Joan Davenport, Carolyn Demoranville

Cranberry Station Best Management Practices Guide - 2000 Edition

Research in WI has shown that cranberries require additions of phosphorus fertilizer for sustained productivity. However, trying to determine the right amount of phosphorus to add and when to add it is very difficult - one of the few aspects of crop management where cranberries have something in common with other crops. What makes the situation extra hard in cranberries is that programs of soil and tissue testing often give conflicting information - it is not uncommon to see soil test values of phosphorus in or above the normal range (20-80 ppm Bray P) and tissue phosphorus contents either at …


The Feasibility Of An Audio-Cassette Research Review Subscription Service For High School Chemistry Teachers., Edgar N. Johnson Jan 1974

The Feasibility Of An Audio-Cassette Research Review Subscription Service For High School Chemistry Teachers., Edgar N. Johnson

Doctoral Dissertations 1896 - February 2014

No abstract provided.


The Effects Of Contingency Management On The Attainment Of Performance Criteria In Teaching High School Chemistry., Pierre. Barrette Jan 1971

The Effects Of Contingency Management On The Attainment Of Performance Criteria In Teaching High School Chemistry., Pierre. Barrette

Doctoral Dissertations 1896 - February 2014

No abstract provided.