Approaches In Molecular Engineering To Optimize The Desired Properties Of Photoactive Molecules,
2022
University of New Mexico - Main Campus
Approaches In Molecular Engineering To Optimize The Desired Properties Of Photoactive Molecules, Douglas Joseph Breen
Chemistry and Chemical Biology ETDs
Within this dissertation, photochemical systems that bear significance to next-generation photonic materials and devices are explored. Notable advances in the design, synthesis, and characterization of three distinct groups of photoactive molecules are achieved through molecular design and spectroscopic analysis. First, novel ruthenium sulfoxide complexes bearing substituted phosphine ligands are found to provide extraordinary control over photoisomerization quantum yields. A comparison of these complexes reveals ground-state characteristics that are instrumental in this reactivity, while a novel spectroscopic technique provides rare structural evidence for an O-bonded metastable isomer. Ruthenium complexes bearing chelating carbene-sulfoxide ligands rapidly thermally revert from the O-bonded metastable isomer …
The Effect Of Fluorinated Substitution Of Meso Phenyl Porphyrins On Porphyrin Basicity,
2022
Nova Southeastern University
The Effect Of Fluorinated Substitution Of Meso Phenyl Porphyrins On Porphyrin Basicity, Harsh Chheda, Rushi Patel, Maria Ballester, Victor Castro
Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures
The purpose of this study was to determine the effects of fluorinated substitution of meso phenyl porphyrins on porphyrin basicity. The protonation of meso-Tetra(2,3,4-trifluoromethylphenyl) porphyrin (TF) and meso-Tetra(pentafluorophenyl) porphyrin (PF) will be studied through UV vis spectroscopy. Protonation is achieved by titration of each porphyrin in toluene with trifluoroacetic acid (TFA). The presence of a wavelength shift from the free base Soret to the protonated Soret will indicate the formation of a dication. The data from the UV spectra will be used to calculate the pKa values associated with each porphyrin. Based on the results, the average pKa for TF …
Comparing And Contrasting Therapeutic Drugs Vs. Lifestyle Changes That Combattype-Ii Diabetes,
2022
Taylor University
Comparing And Contrasting Therapeutic Drugs Vs. Lifestyle Changes That Combattype-Ii Diabetes, Alexander Cline Helmuth
Chemistry & Biochemistry Student Projects
In this thesis, I will be presenting various preventive approaches to combat type-II diabetes. The focus of this paper will be comparing and contrasting therapeutic drug targets such as Metformin and Sulfonylureas that are prescribed for type-II diabetic patients versus taking preventative steps such as making lifestyle changes including weight management, physical activity, and having a balanced diet that prevents onset of type-II diabetes or helps patients manage type-II diabetes. From this paper, one will gain insight on how there are multiple approaches to combat type-II diabetes that are not in the form of the pill.
Microfluidic Paper Analytical Devices,
2022
Taylor University
Microfluidic Paper Analytical Devices, Madison Page
Chemistry & Biochemistry Student Projects
Microfluidic paper analytical devices (µPADs) are small, paper-based matrices similar to Lab-on-a-Chip (LOC). They are capable of semi-quantitative analysis, with applications ranging from medical to environmental to food and beverage testing. Important to improving point-of-care devices (POCs), various techniques have been integrated into µPADs to customize analysis and fit different clinical situations.
The Application Of Biological Processes To Increase Energy Potential In Landfills,
2022
Taylor University
The Application Of Biological Processes To Increase Energy Potential In Landfills, Ashlyn Eisenhart
Chemistry & Biochemistry Student Projects
There has been a dramatic increase in the amount of waste that we humans have created. This has been due to population growth, an increase in industrial manufacturing, along with urbanization and modernization.8 The number of tons of municipal solid waste entering landfills has increased from 82.5 million tons in 1960 to 146.1 million tons in 2018.17 However, thanks to recycling, composting, and energy recovery from combustion, the percentage of solid waste going to landfills has dramatically decreased, from around 93.6 to about 65.4 percent.17
Chemistry Of Toothpaste,
2022
Taylor University
Chemistry Of Toothpaste, Kayla Blanche Kirtley
Chemistry & Biochemistry Student Projects
The chemistry of toothpaste is explained, with a description of the chemical components and their mode of action in the role of toothpaste.
Unraveling Molecular Mechanisms Of Antibiotic Resistance Through Multiscale Simulations And Explainable Machine Learning,
2022
Southern Methodist University
Unraveling Molecular Mechanisms Of Antibiotic Resistance Through Multiscale Simulations And Explainable Machine Learning, Zilin Song
Chemistry Theses and Dissertations
Pathogen resistance to β-lactam antibiotics compromises effective treatments of superbug infections. One major source of β-lactam resistance is the bacterial production of β-lactamases, which could effectively hydrolyze β-lactam drugs. In this thesis, the hydrolysis of various β-lactam antibiotics by class A serine-based β-lactamases (ASβLs) were investigated using hybrid Quantum Mechanical / Molecular Mechanical (QM/MM) minimum energy pathway (MEP) calculations and explainable machine learning (ML) approaches. The TEM-1/benzylpenicillin acylation reaction with QM/MM chain-of-states reaction pathways was firstly revisited. I proposed two decomposition methods for energy contribution analysis based on perturbing ML regression models. Both methods were shown to be model implementation …
In-Situ/Operando57Fe Mössbauer Spectroscopic Technique And Its Applications In Nife-Based Electrocatalysts For Oxygen Evolution Reaction,
2022
1. Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, Liaoning, China;
In-Situ/Operando57Fe Mössbauer Spectroscopic Technique And Its Applications In Nife-Based Electrocatalysts For Oxygen Evolution Reaction, Jafar Hussain Shah, Qi-Xian Xie, Zhi-Chong Kuang, Ri-Le Ge, Wen-Hui Zhou, Duo-Rong Liu, Alexandre I. Rykov, Xu-Ning Li, Jing-Shan Luo, Jun-Hu Wang
Journal of Electrochemistry
The development of highly efficient and cost-effective electrocatalysts for the sluggish oxygen evolution reaction (OER) remains a significant barrier to establish effective utilization of renewable energy storage systems and water splitting to produce clean fuel. The current status of the research in developing OER catalysts shows that NiFe-based oxygen evolution catalysts (OECs) have been proven as excellent and remarkable candidates for this purpose. But it is critically important to understand the factors that influence their activity and underlying mechanism for the development of state-of-the-art OER catalysts. Therefore, the development of in-situ/operando characterizations is urgently required to detect key intermediates along …
Recent Advances In Electrical Transport Spectroscopy For The In Situ Measurement Of Electrochemical Interfaces,
2022
Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, Jiangsu, China;
Recent Advances In Electrical Transport Spectroscopy For The In Situ Measurement Of Electrochemical Interfaces, Zhang-Yan Mu, Meng-Ning Ding
Journal of Electrochemistry
Electrochemical/electrocatalytic technology has played a central role in achieving highly efficient energy conversion and storage. To date, the in-depth electrochemical research begins to require accurate and multi-dimensional information of electrochemical interfaces, which usually relies on the application of in situ characterizations. Electrical transport spectroscopy (ETS) is a newly developed measurement strategy based on chip-platform, and provides in situ information of electrochemical interfaces from a novel perspective due to a signal origin that is fundamentally different from typical spectroscopic and electrochemical techniques. In this tutorial review, the working principle and experimental setup of ETS are described in detail with the demonstration …
An Additive Incorporated Non-Nucleophilic Electrolyte For Stable Magnesium Ion Batteries,
2022
1. College of Materials Science and Engineering, Huaqiao University, Xiamen 361021, Fujian, China;3. i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Science, Suzhou 215123, Jiangsu, China;
An Additive Incorporated Non-Nucleophilic Electrolyte For Stable Magnesium Ion Batteries, Mao-Ling Xie, Jun Wang, Chen-Ji Hu, Lei Zheng, Hua-Bin Kong, Yan-Bin Shen, Hong-Wei Chen, Li-Wei Chen
Journal of Electrochemistry
Non-nucleophilic electrolytes are promising next-generation highly stable electrolytes for magnesium-ion batteries (MIBs). However, a passivation layer on Mg metal anode usually blocks Mg2+ diffusion, leading to poor reaction kinetics and low Coulombic efficiency of the Mg plating/stripping in these electrolytes. Here we explore the utilization of phenyl disulfide (PDF) as a film-forming additive for non-nucleophilic electrolytes to regulate the interfacial chemistry on Mg metal anode. Phenyl-thiolate generated from the PDF additive was found to suppress the unfavorable surface blocking layer, resulted in a high Coulombic efficiency of up to 99.5% for the Mg plating/stripping process as well as a …
Brain Electrochemistry,
2022
1. Beijing National Laboratory for Molecular Science, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, the Chinese Academy of Sciences, Beijing 100190, China;3. University of Chinese Academy of Sciences, Beijing 100049, China;
Brain Electrochemistry, Cong Xu, Ying Jiang, Ping Yu, Lan-Qun Mao
Journal of Electrochemistry
Brain, as the source of neural activities such as perceptions and emotions, consists of the dynamic and complex networks of neurons that implement brain functions through electrical and chemical interactions. Therefore, analyzing and monitoring neurochemicals in living brain can greatly contribute to uncovering the molecular mechanism in both physiological and pathological processes, and to taking a further step in developing precise medical diagnosis and treatment against brain diseases. Through collaborations across disciplines, a handful of analytical tools have been proven to be befitting in neurochemical measurement, spanning the level of vesicles, cells, and living brains. Among these, electrochemical methods endowed …
Tracking Light-Induced Fragmentation Of Single Silver Nanoparticles By Single Entity Electrochemistry,
2022
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, Jiangsu, P. R. China;
Tracking Light-Induced Fragmentation Of Single Silver Nanoparticles By Single Entity Electrochemistry, Mengjie Chen, Si-Min Lu, Hao-Wei Wang, Yi-Tao Long
Journal of Electrochemistry
Light irradiation on silver nanoparticles (Ag NPs) could cause the energy conversion, thus, the fragmentation of Ag NPs. It is important to detect the changes of fragmented Ag NPs in the aspects of physical and chemical properties. Herein, benefiting from the high sensitivity, high temporal resolution, and high-throughput, single entity electrochemistry (SEE) method is introduced to in-situ track the dynamic laser fragmentation of single Ag NP. Compared with UV-Vis absorption spectroscopy and transmission electron microscopy (TEM), SEE methods enables an accurate in-situ measurements of light-induced fragmentation of single Ag NP. The variation in the statistic current amplitude displays the real-time …
Rational Design Of Electrochemical Molecular Probes For Highly Selective And Long-Term Measurement In Vivo,
2022
School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China.;
Rational Design Of Electrochemical Molecular Probes For Highly Selective And Long-Term Measurement In Vivo, Yue Wang, Li-Min Zhang, Yang Tian
Journal of Electrochemistry
Designing electrochemical interfaces for in vivo analysis of neurochemicals with high selectivity and long-term stability is vital for monitoring dynamic variation and dissecting the complex mechanisms of pathogenesis in living animals. This review focuses on the development of electrochemical interfaces based on rational design of molecular probes for in vivo measurement with high selectivity and high stability from three aspects: (1) Specific recognition probes were rationally designed and created to remarkably improve the selectivity of in vivo analysis in a complicated brain environment. (2) The Au-C≡C functionalized surface was developed to remarkably enhance the stability of molecular assembly, and employed …
In Situ Characterization Of Electrode Structure And Catalytic Processes In The Electrocatalytic Oxygen Reduction Reaction,
2022
1. CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Beijing National Laboratory for Molecular Science (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China;2. University of Chinese Academy of Sciences, Beijing 100049, China;
In Situ Characterization Of Electrode Structure And Catalytic Processes In The Electrocatalytic Oxygen Reduction Reaction, Ya-Chen Feng, Xiang Wang, Yu-Qi Wang, Hui-Juan Yan, Dong Wang
Journal of Electrochemistry
As an electrochemical energy conversion system, fuel cell has the advantages of high energy conversion efficiency and high cleanliness. Oxygen reduction reaction (ORR), as an important cathode reaction in fuel cells, has received extensive attention. At present, the electrocatalysts are still one of the key materials restricting the further commercialization of fuel cells. The fundamental understanding on the catalytic mechanism of ORR is conducive to the development of electrocatalysts with the enhanced activity and high selectivity. This review aims to summarize the in situ characterization techniques used to study ORR. From this perspective, we first briefly introduce the advantages of …
Synchrotron X-Rays Characterizations Of Metal-Air Batteries,
2022
1. MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, Harbin Institute of Technology, Harbin 150001, Heilongjiang, China;
Synchrotron X-Rays Characterizations Of Metal-Air Batteries, Ya-Jie Song, Xue Sun, Li-Ping Ren, Lei Zhao, Fan-Peng Kong, Jia-Jun Wang
Journal of Electrochemistry
The rapid development of electric vehicles urgently requires high-energy-density batteries. Recently, metal-air batteries have attracted much attention in industry and academia for their ultra-high theoretical energy densities. However, the practical application of metal-air batteries is severely impeded by multiple drawbacks, including severe side reactions, low energy efficiency, and limited cycle life. Understanding the reaction mechanism of the cell and further developing effective strategies are beneficial for the practical application of metal-air batteries. In the past decade, advanced characterization techniques have accelerated the development of metal-air batteries. In particular, synchrotron radiation-based characterization techniques have been widely applied to the mechanistic study …
The Effect Of Fluorinated Substitution Of Meso Phenyl Porphyrins On Porphyrin Basicity,
2022
Nova Southeastern University
The Effect Of Fluorinated Substitution Of Meso Phenyl Porphyrins On Porphyrin Basicity, Harsh Chheda, Rushi Patel, Maria Ballester Ph.D., Victor Castro Ph.D.
Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures
The protonation of meso-Tetra(2,3,4-trifluoromethylphenyl) porphyrin (TF) and meso-Tetra(pentafluorophenyl) porphyrin (PF) will be studied through UV vis spectroscopy. Protonation is achieved by titration of each porphyrin in toluene with trifluoroacetic acid (TFA). The presence of a wavelength shift from the free base Soret to the protonated Soret will indicate the formation of a dication. The data from the UV spectra will be used to calculate the pKa values associated with each porphyrin. Based on the results, the average pKa for TF upon protonation was 2.07, while the average pKa for PF was 1.36 over four trials. A greater acidic value for …
The Phase Diagram Of A Non-Ideal Mixture’S P − V − X 2-Component Gas=Liquid Representation, Including Azeotropes,
2022
University of Connecticut
The Phase Diagram Of A Non-Ideal Mixture’S P − V − X 2-Component Gas=Liquid Representation, Including Azeotropes, Carl W. David
Chemistry Education Materials
The liquid=vapor two phase p−v−x diagram is constructed for non-ideal solutions including azeotropes.
Recent Advances In Structural Regulation On Non-Precious Metal Catalysts For Oxygen Reduction Reaction In Alkaline Electrolytes,
2022
1. State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences, Changchun 130022, Jilin, China;2. University of Science and Technology of China, Hefei 230026, Anhui, China;
Recent Advances In Structural Regulation On Non-Precious Metal Catalysts For Oxygen Reduction Reaction In Alkaline Electrolytes, Xue Wang, Li Zhang, Chang-Peng Liu, Jun-Jie Ge, Jian-Bing Zhu, Wei Xing
Journal of Electrochemistry
Oxygen reduction reaction (ORR) in alkaline electrolytes is an important electrochemical process for metal-air batteries and anion exchange membrane fuel cells (AEMFCs). However, the sluggish kinetics spurs intensive research on searching robust electrocatalysts. Non-precious metal catalysts (NPMCs) that can circumvent the cost and scarcity issues associated with platinum (Pt)-based materials have been pursued and the challenges lie in the performance improvement to rival Pt-based benchmarks. As the composition and structure of the NPMCs have a significant impact on the catalytic performance, precise regulation on the catalyst structure holds great promise to bridge the activity gap between NPMCs and Pt-based benchmarks. …
Magnetic Resonance In Metal-Ion Batteries: From Nmr (Nuclear Magnetic Resonance) To Epr (Electron Paramagnetic Resonance),
2022
Shanghai Key Laboratory of Magnetic Resonance, State Key Laboratory of Precision Spectroscopy, School of Physics and Electronic Science, East China Normal University, Shanghai 200241, P. R. China;
Magnetic Resonance In Metal-Ion Batteries: From Nmr (Nuclear Magnetic Resonance) To Epr (Electron Paramagnetic Resonance), Bing-Wen Hu, Chao Li, Fu-Shan Geng, Ming Shen
Journal of Electrochemistry
Metal-ion batteries have changed our quotidian lives. The research on the electrode materials for metal-ion battery is the key to improve the performance of the battery. Therefore, understanding the structure-performance relationship of the electrode materials can help to improve the energy density and power density of the materials. Magnetic resonance, including nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR), has been continuously improved during the past three decades, and has gradually become one of the important technologies to study the structure-performance relationship of electrode materials. This paper summarizes the progress of magnetic resonance research from our group on several …
Recent Advances In Electrochemical Kinetics Simulations And Their Applications In Pt-Based Fuel Cells,
2022
1. Collaborative Innovation Center of Chemistry for Energy Material, Key Laboratory of Computational Physical Science (Ministry of Education), Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Shanghai 200433, China;
Recent Advances In Electrochemical Kinetics Simulations And Their Applications In Pt-Based Fuel Cells, Ji-Li Li, Ye-Fei Li, Zhi-Pan Liu
Journal of Electrochemistry
Theoretical simulations of electrocatalysis are vital for understanding the mechanism of the electrochemical process at the atomic level. It can help to reveal the in-situ structures of electrode surfaces and establish the microscopic mechanism of electrocatalysis, thereby solving the problems such as electrode oxidation and corrosion. However, there are still many problems in the theoretical electrochemical simulations, including the solvation effects, the electric double layer, and the structural transformation of electrodes. Here we review recent advances of theoretical methods in electrochemical modeling, in particular, the double reference approach, the periodic continuum solvation model based on the modified Poisson-Boltzmann …
