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The Reveal: A Technical Study And Conservation Treatment Of An Overpaint Portrait, Camille Ferrer 2024 SUNY University at Buffalo

The Reveal: A Technical Study And Conservation Treatment Of An Overpaint Portrait, Camille Ferrer

Art Conservation Master's Projects

A severely damaged 19th-century oil painting depicting a portrait of a woman was treated at Patricia H. and E. Garman Art Conservation Department. A typed letter provided by the owner mentioned that it has been previously restored yet returned with unsatisfactory results. After further examination, the painting appeared to have been previously treated multiple times by different people. There was overpaint distinctly present on the face and later discovered to be present overall. The full state of condition of the painting was initially unknown due to the sum of the surface being overpainted. However, there were evidence of paint loss …


Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel 2024 University of New Mexico

Excited State Processes In Radical Elaborated Platinum Donor-Acceptor Complexes, Sangita Paudel

Chemistry and Chemical Biology ETDs

Organo-transition metal complexes are being widely studied to understand their photophysical properties for their wide range of applications as efficient emitters in organic light emitting diodes (OLEDs), light emitting electrochemical cells (LEECs), etc. Cyclometalated organo-transition metal complexes such as cyclometalated square planar platinum(II) complexes are becoming suitable candidates for such applications because of their highly efficient luminescence. Understanding the excited properties of such complexes is useful in designing highly efficient and color tunable phosphors with desired excited state lifetimes. We aim to explore the influence of radical substituents on electronic structure, luminescence quantum efficiencies, and excited state lifetimes by synthesizing …


Purification And Isolation Of Α-Chloro-Β-Lactone Precursor Molecules, Matthew Ellis 2024 Bridgewater College

Purification And Isolation Of Α-Chloro-Β-Lactone Precursor Molecules, Matthew Ellis

Honors Projects

This research investigates the synthesis of α-chloro-β-lactone molecules, focusing on the production, isolation, and purification of two precursor compounds from chloroacetic acid and substituted benzaldehydes. While multiple methods were explored, including EDC, DIC, and DCC catalysis, DCC proved to be most effective in producing higher yields. However, challenges in purification arose due to the formation of byproducts, particularly with DCC, prompting further investigation for efficient extraction and purification techniques. DCC, however, shows a promising route for α-chloro-β-lactone synthesis, despite purification complexities.


Investigations Of The Eutectic Formation And Skin Rejuvenation By Hyaluronan - Kojic Acid Dipalmitate System, Syed Waqar Hussain Shah, Sumbal Imran, Iram Bibi, Kashif Ali, Nadia Bashir 2024 Department of Chemistry, Hazara University, Mansehra, Pakistan

Investigations Of The Eutectic Formation And Skin Rejuvenation By Hyaluronan - Kojic Acid Dipalmitate System, Syed Waqar Hussain Shah, Sumbal Imran, Iram Bibi, Kashif Ali, Nadia Bashir

Karbala International Journal of Modern Science

Eutectic phenomenon has been investigated in binary system based on biopolymer hyaluronan (HN) and kojic acid dipalmitate (KAD). Solid-liquid phase diagram showed a significant dependence of melting points on weight fraction of KAD up to KAD < 0.5. A negligible regain to melting temperature of pure KAD occurred later. Simulations of molecular mechanics using a four-unit segment of HN and KAD revealed the interaction between carbonyl of KAD with 4-OH on N-acetylglucosamine unit of oligomer. Infrared vibrational spectroscopy also endorsed the existence of a weakly interacting system. Such behavior was expected due to steric hinderance and rigidity of biopolymer. The thermal decomposition temperature of HN (i.e., 215 °C) was increased to 322 °C in HK50 having HN and KAD in 1:50 w/w. Bioelectric impedance analysis revealed that these green materials could promote skin health in humans.


Synthesis And Characterization Of Renewable Heterogeneous Catalyst Zno Supported Biogenic Silica From Pineapple Leaves Ash For Sustainable Biodiesel Conversion, Nadila Pratiwi, Suriati Eka Putri, Yulia Shinta, Arya Ibnu Batara, Diana Eka Pratiwi, Abd Rahman, Nur Ahmad, Heryanto Heryanto 2024 Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Negeri Makassar, Makassar, South Sulawesi, Indonesia;

Synthesis And Characterization Of Renewable Heterogeneous Catalyst Zno Supported Biogenic Silica From Pineapple Leaves Ash For Sustainable Biodiesel Conversion, Nadila Pratiwi, Suriati Eka Putri, Yulia Shinta, Arya Ibnu Batara, Diana Eka Pratiwi, Abd Rahman, Nur Ahmad, Heryanto Heryanto

Karbala International Journal of Modern Science

This study reports on the first case of the low-cost and environmentally friendly ZnO/SiO2 heterogeneous catalyst from pineapple leaves ash (PLA). Catalyst shows excellent performance in catalyzing the transesterification of waste cooking oil (WCO) with methanol for biodiesel conversion. This study focuses on assessing the influence of Zn content on physicochemical characteristics, using XRD, FTIR, SEM, and N2 adsorption-desorption methods. In addition, three different Zn content levels (20, 25, and 30 %wt) were applied. The results showed that all ZnO/SiO2 samples exhibited characteristics suitable for use as catalyst with an average crystallite size of 31.83-34.15 nm, and a surface area …


Univariate Optimization Of Dispersive Liquid-Liquid Microextraction For Preconcentration Of Lead From Environmental Matrices, Samawah Region Prior To Quantification Using Flame Atomic Absorption Spectroscopy, Zaman Sahb Mehdi, Saher A. Ali Alshamkhawy 2024 Department of Chemistry, College of Science, University of Thi-Qar, Thi-Qar, 64001, Iraq.

Univariate Optimization Of Dispersive Liquid-Liquid Microextraction For Preconcentration Of Lead From Environmental Matrices, Samawah Region Prior To Quantification Using Flame Atomic Absorption Spectroscopy, Zaman Sahb Mehdi, Saher A. Ali Alshamkhawy

Al-Bahir Journal for Engineering and Pure Sciences

In this work, a procedure based on dispersive liquid₋liquid microextraction for lead (Pb) preconcentration and quantification in an environmental matrix by flame atomic absorption spectroscopy (FAAS) was applied. A case-study approach was chosen to obtain further in-depth information on the Pb levels. The green chemistry principles have been applied for the pretreatment and preparation of real samples by focusing on some features such as the volume of reagents/sample, employ of energy efficient equipment, and production of waste. A univariate strategy was utilized to achieve the optimum extraction conditions. 1750 µL of acetonitrile containing 100 µL of carbon tetrachloride, were rapid …


Butterworth Filter To Reduce Reactivity Fluctuations, Daniel Suescún-Díaz, Geraldyne Ule-Duque, Luis E. Cardoso-Páez 2024 Department of Natural Sciences, Avenida Pastrana, Universidad Surcolombiana, Neiva, Huila, Colombia

Butterworth Filter To Reduce Reactivity Fluctuations, Daniel Suescún-Díaz, Geraldyne Ule-Duque, Luis E. Cardoso-Páez

Karbala International Journal of Modern Science

In this study, we introduce the calculation of reactivity in nuclear reactors. The proposed method uses the Euler-Maclaurin series to approximate the integral in the inverse equation of point kinetics. The approximation is done with the first three terms, the first term represents the approximation of a zero-order sum, the second term the trapezoidal rule and the third term the first Bernoulli number. These three terms improve the approximation, along with an estimate of the neutron density using the prompt jump approximation. To reduce neutron density fluctuations, a second-order Butterworth filter for the reactivity calculation was implemented, which offers the …


Newfeaturesoflaboratory-Generatedepfrsfrom1,2-Dichlorobenzene(Dcb)And2‑Monochlorophenol(Mcp), Lavrent Khachatryan, Marwan Y. Rezk, Divine Nde, Farhana Hasan, Slawomir Lomnicki, Dorin Boldor, Robert Cook, Phillip Sprunger, Randall W. Hall, Stephania Cormier 2024 Louisiana State University at Baton Rouge

Newfeaturesoflaboratory-Generatedepfrsfrom1,2-Dichlorobenzene(Dcb)And2‑Monochlorophenol(Mcp), Lavrent Khachatryan, Marwan Y. Rezk, Divine Nde, Farhana Hasan, Slawomir Lomnicki, Dorin Boldor, Robert Cook, Phillip Sprunger, Randall W. Hall, Stephania Cormier

Natural Sciences and Mathematics | Faculty Scholarship

The present research is primarily focused on investigating the characteristics of environmentally persistent free radicals (EPFRs) generated from commonly recognized aromatic precursors, namely, 1,2-dichlorobenzene (DCB) and 2- monochlorophenol (MCP), within controlled laboratory conditions at a temperature of 230 °C, termed as DCB230 and MCP230 EPFRs, respectively. An intriguing observation has emerged during the creation of EPFRs from MCP and DCB utilizing a catalyst 5% CuO/SiO2, which was prepared through various methods. A previously proposed mechanism, advanced by Dellinger and colleagues (a conventional model), postulated a positive correlation between the degree of hydroxylation on the catalyst’s surface (higher hydroxylated, HH and …


Machine Learning Model And Molecular Docking For Screening Medicinal Plants As Hiv-1 Reverse Transcriptase Inhibitors, Muthia Rahayu Iresha, Firdayani Firdayani, Agam Wira Sani, Nihayatul Karimah, Shelvi Listiana, Irfansyah Yudhi Tanasa, Arief Sartono, Ayu Masyita 2024 Research Center for Vaccine and Drugs, National Research and Innovation Agency (BRIN), South Tangerang, Indonesia

Machine Learning Model And Molecular Docking For Screening Medicinal Plants As Hiv-1 Reverse Transcriptase Inhibitors, Muthia Rahayu Iresha, Firdayani Firdayani, Agam Wira Sani, Nihayatul Karimah, Shelvi Listiana, Irfansyah Yudhi Tanasa, Arief Sartono, Ayu Masyita

Karbala International Journal of Modern Science

The human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) plays a significant role in viral replication and is one of the targets for anti-HIV. However, a mutation in viral strains rapidly developed the resistance of the com-pounds to the protein, reducing the effectiveness of the inhibitors. This work seeks to utilize machine learning-based quantitative structure-activity relationship (QSAR) analysis in combination with molecular docking simulations to forecast the presence of active compounds derived from medicinal plants. Specifically, the objective is to identify com-pounds that have the potential to operate as inhibitors of HIV-1 reverse transcriptase (RT), encompassing both wild-type and …


Historical Ozone Isopleths For Salt Lake Valley, Ut, Usa, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen 2024 Brigham Young University - Provo

Historical Ozone Isopleths For Salt Lake Valley, Ut, Usa, Callum Flowerday, Isaac Sudweeks, Brad Adams, Jaron C. Hansen

ScholarsArchive Data

EPA quality assured data, collected by the Utah Division of Air Quality, was used for this analysis.


Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster 2024 Brigham Young University - Provo

Historical Analysis Of Urban Dust Generated By The Great Salt Lake Playa, Callum Flowerday, Jaron C. Hansen, Rebekah Stanley, Kaitlyn Brewster

ScholarsArchive Data

Historical PM10 filters, provided by the Utah Division of Air Quality, were analyzed for elemental composition of various metals. This was done using ICP-MS.

Also included, EPA PM10 historical data and bathymetry data provided by the Utah USGS.


Maximizing Charge Dynamics In Znin2s4/Cn Van Der Waals Heterojunction For Optimal Hydrogen Production From Photoreforming Of Glucose, Jinqiang Zhang, Xinyuan Xu, Lei Shi, Huayang Zhang, Shaobin Wang, Hongqi Sun 2024 Edith Cowan University

Maximizing Charge Dynamics In Znin2s4/Cn Van Der Waals Heterojunction For Optimal Hydrogen Production From Photoreforming Of Glucose, Jinqiang Zhang, Xinyuan Xu, Lei Shi, Huayang Zhang, Shaobin Wang, Hongqi Sun

Research outputs 2022 to 2026

Biomass photoreforming stands out as a promising avenue for green hydrogen, leveraging solar energy for the generation and transformation of clean and renewable energy resources. The pursuit of efficient photocatalysts is motivated by the unsatisfied hydrogen evolution performance arising from the complex and stubborn structure of biomass. Herein, we loaded 2-dimensional (2D) ZnIn2S4 onto 2D carbon nitride nanosheets, resulting in the formation of Van der Waals (VDW) heterojunctions (ZIS/CN). Band structure and morphology of CN were rationally tailored through precursor engineering to effectively magnify interfacial internal electric field and minimize diffusion pathway within the VDW heterostructure, realizing optimal charge dynamics …


Multi-Agent System For Portfolio Profit Optimization For Future Stock Trading, Usha Devi, Mohan R 2024 Department of Computer Science and Engineering, National Institute of Technology Tiruchirappalli, Tuvakudi, India.

Multi-Agent System For Portfolio Profit Optimization For Future Stock Trading, Usha Devi, Mohan R

Karbala International Journal of Modern Science

Stock trading highly contributes to the economic growth of the country. The stock trading objective is to earn profits with buy/sell/hold decisions on the set of stocks in the portfolio. The portfolio optimization problem is finding the decision sequence that leads to higher profit and lower risk. Portfolio optimization is challenging due to complex price history patterns and an uncertain environment. Incorrect decisions in stock trading lead to massive losses. The proposed Multi-Agent System for Portfolio Profit Optimization (MASPPO) aims to optimize trading profit and reduce risk with accurate predictions. The proposed model integrates the Fuzzy c-means with the Deep …


College Of Natural Sciences 2023 Year-End Publication, College Of Natural Sciences 2024 South Dakota State University

College Of Natural Sciences 2023 Year-End Publication, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 3 Department Highlights
Page 4 One Day for State
Page 5 Noble Prize Winner Speaks on Campus
Page 6-7 Faculty Excellence
Page 8-9 Student Excellence
Page 10 Outreach Program
Page 10 Events and Traditions
Page 11 Connections Abroad
Page 12 Student Spotlight
Page 13 Alumni Spotlight
Page 14 First Ever Drone Day
Page 15 Grand Opening of POET Bioproducts Center
Page 16 Work Anniversaries


Rational Design Of Peptide-Based Materials Informed By Multiscale Molecular Dynamics Simulations, Dhwanit Rahul Dave 2024 The Graduate Center, City University of New York

Rational Design Of Peptide-Based Materials Informed By Multiscale Molecular Dynamics Simulations, Dhwanit Rahul Dave

Dissertations, Theses, and Capstone Projects

The challenge of establishing a sustainable and circular economy for materials in medicine and technology necessitates bioinspired design. Nature's intricate machinery, forged through evolution, relies on a finite set of biomolecular building blocks with through-bond and through-space interactions. Repurposing these molecular building blocks requires a seamless integration of computational modeling, design, and experimental validation. The tools and concepts developed in this thesis pioneer new directions in peptide-materials design, grounded in fundamental principles of physical chemistry. We present a synergistic approach that integrates experimental designs and computational methods, specifically molecular dynamics simulations, to gain in-depth molecular insights crucial for advancing the …


Stereospecific Cross-Coupling Reactions Of Vinyl Triflates And An Investigation Of The Synthesis And Reactivity Of Activated Alkyltricyclohexylstannanes, Pejman Ghaemimohammadi 2024 The Graduate Center, City University of New York

Stereospecific Cross-Coupling Reactions Of Vinyl Triflates And An Investigation Of The Synthesis And Reactivity Of Activated Alkyltricyclohexylstannanes, Pejman Ghaemimohammadi

Dissertations, Theses, and Capstone Projects

Organic chemistry exists in all aspects of everyday life from polymers to pharmaceutics. Formation of carbon-carbon bonds is essential for the synthesis of complex organic compounds. This goal can be achieved by using transition metal catalysts. Second-row transition metals such as Pd, Pt, Rh, and Ir have shown remarkable efficacy in these reactions. Metal-catalyzed cross-coupling reactions form carbon-carbon bonds between electrophiles and nucleophiles using transition metal catalysts. Pd is mainly used in this reaction.

Transition metal-catalyzed cross-coupling reactions that form a bond between two C(sp2) carbons have been widely studied over the past decades. C(sp2)-C(sp3 …


Evaluating The Reliability And Accuracy Of Alchemical Binding Free Energy Methods And Calculations, Fnu Sheenam 2024 The Graduate Center, City University of New York

Evaluating The Reliability And Accuracy Of Alchemical Binding Free Energy Methods And Calculations, Fnu Sheenam

Dissertations, Theses, and Capstone Projects

Molecular recognition plays a crucial role in various biological processes, such as enzymatic reactions, signal transduction, and genetic information processing. Investigating how proteins selectively bind to their partners is an active research area, but there is a lack of experimental details on protein structures and interactions in molecular complexes. Computational techniques based on macromolecular structures offer a way to predict protein-ligand interactions and explore their recognition mechanisms. Estimating binding affinities, particularly through alchemical binding free energy calculations, has become valuable in supporting drug discovery. This work introduces new methodologies, utilizing the Alchemical Transfer Method, to address issues like poor convergence …


The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark 2024 University of Missouri

The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark

Undergraduate Research Symposium

The aim of this research project is to expand the scope of 4 + 3 cycloadduct chemistry by varying functional groups attached to the prerequisite oxidopyridinium ion for each respective cycloadduct product. While N-substitution of the pyridinium precursor is known to proceed smoothly if alkylated by a lone methyl group, we evaluated the effect a larger alkyl group would have on the overall yield of the 4 + 3 cycloadduct product.

Isobutyl triflate, generated from the known reaction between isobutyl alcohol and triflic anhydride, was reacted with ethyl 5-hydroxy-nicotinate to generate the respective N-isobutyl oxidopyridinium ion in quantitative …


The Roaring Lion Of Berlin: The Life, Thought, And Influence Of Eugen Dühring, Arden Roy 2024 University of Missouri, St. Louis

The Roaring Lion Of Berlin: The Life, Thought, And Influence Of Eugen Dühring, Arden Roy

Undergraduate Research Symposium

The life and influence of 19th-century German polymath Eugen Dühring remain but a mere footnote in the history of ideas, being primarily relegated to the status of little more than a theoretical rival to Marxism in the German socialist movement and the occasional object of Freidrich Nietzsche's rhetorical flogging. Despite the current consensus on the subject, Eugen Dühring was a scholar of vast, remarkable learnedness, contributing greatly to philosophy, economics, and the natural sciences. The aim of this talk will be to clear the fog surrounding the life and work of the controversial blind scholar and give an account of …


Etherification Of Propargylic Alcohol Using Ferrocenium Ions, Cody Amann, Sai Anvesh Bezawada, Eike B. Bauer 2024 University of Missouri-St. Louis

Etherification Of Propargylic Alcohol Using Ferrocenium Ions, Cody Amann, Sai Anvesh Bezawada, Eike B. Bauer

Undergraduate Research Symposium

Etherification of Propargylic Alcohol using Ferrocenium Ions

Cody Amann, Sai Anvesh Bezawada and Eike B. Bauer*

Department of Chemistry and Biochemistry, University of Missouri-St.Louis, MO 63121

Our research efforts are directed toward the improvement of iron-based catalyst systems. The Bauer research group recently found that the ferrocenium cation is a catalytically active in the etherification of propargylic alcohols. My research was to compare the effect of two different counteranions of the ferrocenium cation on the catalytic activity. Etherification test reactions were performed using 2-methyl-2-phenol-propargylic alcohol and n-butanol to afford the corresponding propargylic ether substitution products. The complexes used …


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