Developing Covalent-Organic Frameworks For Protecting Against Radiation,
2021
University of South Carolina - Columbia
Developing Covalent-Organic Frameworks For Protecting Against Radiation, Megan J. Francis
Senior Theses
This research focuses on the development of lightweight, thermostable dual-function materials for secondary radiation protection and sensing by the integration of hydrogen-rich aliphatic chains inside the porous matrix of covalent-organic frameworks (COFs). The main aims of this project are the synthesis of organic linkers for forming a robust porous COF, synthesizing the porous COF through a condensation reaction, the development of hydrogen-rich aliphatic chains, and integration of aliphatic chains into COFs through click chemistry. This manuscript outlines the methodology and development of a novel self-assembled crystalline, porous material engineered to combine the functions of a shield and sensitive dosimeter. The …
Hemoglobin-Modified Core–Shell Fe3o4@Au Nanostructures For The Electrochemical Detection Of Acrylamide,
2021
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia
Hemoglobin-Modified Core–Shell Fe3o4@Au Nanostructures For The Electrochemical Detection Of Acrylamide, Endang Saepudin, Tri Yuliani, Mochammad Arfin Fardiansyah Nasution, Munawar Khalil, Jong Wook Hong, Tribidasari Anggraningrum Ivandini
Makara Journal of Science
In this study, electrochemical detection of acrylamide using hemoglobin (Hb)-modified core–shell Fe3O4@Au nanostructures was conducted. Fe3O4 nanoparticles (~4.9 nm) and core–shell Fe3O4@Au (5.0–6.4 nm) nanostructures were successfully synthesized by the thermal decomposition method. Electrochemical investigation revealed that the optimum amount of Hb of 2 mg/mL could be immobilized in 0.1 M acetate buffer solution (pH = 6). Moreover, the detection of acrylamide using Fe3O4@Au/Hb was evaluated by the cyclic voltammetry technique. A linear calibration curve (R2 = 0.98) in the concentration range of …
Effects Of Different Extraction Solvents On The Extractive Removal And Properties Of Oil Palm Empty-Fruit Bunch Cellulosic Nanofibers,
2021
Department of Forest Products, Faculty of Forestry, Institut Pertanian Bogor, Bogor 16680, Indonesia
Effects Of Different Extraction Solvents On The Extractive Removal And Properties Of Oil Palm Empty-Fruit Bunch Cellulosic Nanofibers, Achmad Solikhin, Yusuf Sudo Hadi, Muh Yusram Massijaya, Siti Nikmatin
Makara Journal of Science
In this study, the effect of different extraction solvents on the isolation and properties of cellulosic nanofibers (CNFs) were investigated. The unextracted and different solvent-extracted CNFs formed horn-like features and irregularly aggregated nanofibers after oven drying. Scanning electron microscopy at 10000× magnification revealed the smooth external surfaces of all extracted CNFs; this finding is attributed to the limited deposition of amorphous lignocellulosic components on the fibers. All resultant CNF solutions revealed aggregation, with a particle size distribution and zeta average of 21.39–513.00 nm and 162.26–342.13 nm, respectively. Extraction with different solvents and chemical treatment yielded CNF solutions with good transparency. …
Controlling Degradation With Force And Light,
2021
The University of Southern Mississippi
Controlling Degradation With Force And Light, Brad Davis
Dissertations
Stimuli-responsive polymers respond to changes in their environment by altering their physical and chemical properties. Their responsiveness allows them to be used as sensors, mechanical actuators, delivery systems, and can yield either elongated lifetimes through healing mechanisms or shortened lifetimes through triggered degradation. Still a growing field in polymer science, researchers seek to expand the capabilities of these materials by improving their specificity, range, and mechanisms of both the stimuli and the response. The work presented explores stimuli-responsive materials, focusing on mechanical and light stimuli, and how to gain control of the response by specific changes in the polymeric material. …
Two-Dimensional Monolayer Salt Nanostructures Can Spontaneously Aggregate Rather Than Dissolve In Dilute Aqueous Solutions,
2021
Ningbo University
Two-Dimensional Monolayer Salt Nanostructures Can Spontaneously Aggregate Rather Than Dissolve In Dilute Aqueous Solutions, Wenhui Zhao, Yunxiang Sun, Weiduo Zhu, Jian Jiang, Xiaorong Zhao, Dongdong Lin, Wenwu Xu, Xiangmei Duan, Joseph S. Francisco, Xiao Cheng Zeng
Xiao Cheng Zeng Publications
It is well known that NaCl salt crystals can easily dissolve in dilute aqueous solutions at room temperature. Herein, we reported the first computational evidence of a novel salt nucleation behavior at room temperature, i.e., the spontaneous formation of two-dimensional (2D) alkali chloride crystalline/non-crystalline nanostructures in dilute aqueous solution under nanoscale confinement. Microsecond-scale classical molecular dynamics (MD) simulations showed that NaCl or LiCl, initially fully dissolved in confined water, can spontaneously nucleate into 2D monolayer nanostructures with either ordered or disordered morphologies. Notably, the NaCl nanostructures exhibited a 2D crystalline square-unit pattern, whereas the LiCl nanostructures adopted non-crystalline 2D hexagonal …
Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology,
2021
CUNY Graduate Center
Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang
Dissertations, Theses, and Capstone Projects
Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …
Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules,
2021
CUNY Graduate Center
Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles
Dissertations, Theses, and Capstone Projects
Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these …
Synthesis, Characterization And Applications Of Europium Based Perovskite Oxide Nanoparticles,
2021
CUNY Graduate Center
Synthesis, Characterization And Applications Of Europium Based Perovskite Oxide Nanoparticles, Nasim Farahmand
Dissertations, Theses, and Capstone Projects
The synthesis and characterization of nanocrystalline transition and rare-earth metal oxides have been studied widely over the past years. These materials possess unique physical, chemical, magnetic and dielectric properties which make them potential candidates for a wide range of applications such as electronics, energy storage and photocatalysis. There are a number of synthesis methods for preparing these materials, where most of them require stringent conditions such as high pressure and high temperature. However, in this study, a modified sol-gel synthesis has been used with a lower calcination temperature to make uniform nanocrystals of the transition/rare-earth metal oxide family. The focus …
Enhanced Platinum (Ii) Drug Delivery For Anti-Cancer Therapy,
2021
CUNY Graduate Center
Enhanced Platinum (Ii) Drug Delivery For Anti-Cancer Therapy, Marek T. Wlodarczyk
Dissertations, Theses, and Capstone Projects
Over the years, anti-cancer therapies have improved the overall survival rate of patients. Nevertheless, the traditional free drug therapies still suffer from side effects and systemic toxicity, resulting in low drug dosages in the clinic. This often leads to suboptimal drug concentrations reaching cancer cells, contributing to treatment failure and drug resistance. Among available anti-cancer therapies, metallodrugs are of great interest. Platinum (II)-based agents are highly potent and are used to treat many cancers, including ovarian cancer (OC). Cisplatin (cis-diaminedichloroplatinum (II)) is the first Food and Drug Administration (FDA)-approved metallodrug for treatment of solid tumors, and its mechanism …
Modeling Vitexin And Isovitexin Flavones As Corrosion Inhibitors For Aluminium Metal,
2021
Department of Pure and Industrial Chemistry, Bayero University, Kano, Nigeria
Modeling Vitexin And Isovitexin Flavones As Corrosion Inhibitors For Aluminium Metal, Abdullahi Muhammad Ayuba, Umaru Umar
Karbala International Journal of Modern Science
Theoretically, the aluminium corrosion inhibitive performance of vitexin (VTX) and isovitexin (SVT) were evaluated with a view of establishing the mechanism of the inhibition process. Calculations which include the consideration of several global descriptors were studied to describe and correlate the reactivity of the molecules with the computed descriptors. First and second-order condensed Fukui functions were employed to analyze local reactivity parameters, while simulations involving the adsorbed molecules on Al (1 1 0) surface were conducted through quench dynamic simulations and the mechanism of physical adsorption was established with SVT relatively been a better inhibitor on Al surface than VTX.
High Speed Impact On Graphene Composites,
2021
Kennesaw State University
High Speed Impact On Graphene Composites, Giovanny A. Espitia
Symposium of Student Scholars
Since the isolation of Graphene occurred in 2004, numerous studies attempting to exploit the properties of this carbon allotrope have been conducted. Graphene exists in a 2-D manner with sp2 bonds, which provides the allotrope with great electrical, conductive, and mechanical properties. In this paper however, we will focus on the latter in order to examine the feasibility of graphene composites for bulletproof material in the military. Pure graphene sheets count with high porosity density that leads to structural defects as well as poor mechanical properties due to physical contact being sole retainer. For this reason, the selected composite is …
Activated Carbon Pore Expansion Using Acidic Hydrothermal Method,
2021
Kennesaw State University
Activated Carbon Pore Expansion Using Acidic Hydrothermal Method, Max Thompson
Symposium of Student Scholars
Petroleum Coke is a widely abundant, high carbon content material produced as a byproduct of the oil refining process. Its abundance makes the price per ton low and it is produced in almost all regions of the world. Due to the low price and high carbon percentage, commercial companies make large amounts of activated carbon using petroleum coke as a precursor. These activated carbons are characterized by their high surface area and can achieve widely varying pore morphology with different activation processes. The goal of this work is to achieve a homologous mesopore activated carbon material for use in super …
Solid-State Redox Synthesis Of Layered Birnessite-Type Manganese Dioxide (Δ-Mno2) As Aqueous Supercapacitor Electrodes,
2021
Kennesaw State University
Solid-State Redox Synthesis Of Layered Birnessite-Type Manganese Dioxide (Δ-Mno2) As Aqueous Supercapacitor Electrodes, Armando Rodriguez Campos
Symposium of Student Scholars
Nanostructured manganese dioxides are attractive cathode materials in aqueous supercapacitors due to their low cost, environmental benign nature, high theoretical gravimetric capacitance, and power in neutral aqueous electrolytes. In this work, a layered birnessite-type manganese dioxide (δ-MnO2) is synthesized utilizing solid-state redox method with superoxide. The effects of temperature and oxidant amount on the physicochemical properties of δ-MnO2 are characterized using Elemental Dispersion X-ray (EDX) spectroscopy, X-ray diffraction (XRD), N2-sorption, and Scanning Electron Microscope (SEM). The physiochemical properties that are specifically analyzed by varying synthesis conditions pertain to the chemical composition, morphology, and surface area …
One-Pot Synthesis Of Fe2O3@Fe-N-C Oxygen Reduction Electrocatalyst And Its Performance For Zinc-Air Battery,
2021
College of Energy, Xiamen University, Xiamen 361005, Fujian, China;
One-Pot Synthesis Of Fe2O3@Fe-N-C Oxygen Reduction Electrocatalyst And Its Performance For Zinc-Air Battery, Hua Lin, Yi-Jin Wu, Jun-Tao Li, Yao Zhou
Journal of Electrochemistry
Oxygen reduction reaction (ORR) plays a profound role in determining cathode performance in metal-air batteries and fuel cells. Owing to its inherently sluggish kinetics, high-performance ORR catalysts which favors the scissoring of O-O bond and formation of O-H bond are a requisite. In this regard, Pt has been explored as the most efficient ORR electrocatalysts. Nevertheless, due to its expensiveness, the usage of Pt catalysts represents one of the major sources of cost in those energy conversion devices. Thus, the development of alternative ORR electrocatalysts with minimized Pt utilization has been widely pursued over the past few decades. Metal-nitrogen-carbon catalysts …
Study On Mxene-Carbon Black/Sulfur Composite In Integrated Electrode Of Lithium-Sulfur Batteries,
2021
1. Collaborative Innovation Center of Sustainable Energy Materials, Guangxi University, Nanning 530004, Guangxi, China;2. School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, Guangxi, China;
Study On Mxene-Carbon Black/Sulfur Composite In Integrated Electrode Of Lithium-Sulfur Batteries, Ye-Peng Fan, Ye-Qiang Luo, Pei-Kang Shen
Journal of Electrochemistry
Lithium-sulfur (Li-S) batteries are considered as a promising energy storage device due to their ultrahigh theoretical energy density of 2500 Wh·kg-1 and low cost. However, the practical application of Li-S batteries is seriously limited by their low actual energy density, the shuttle effect of polysulfides (LiPSs), and the insulating nature of sulfur and lithium sulfides. Carbon materials have been developed in the design of sulfur hosts due to their adjustable pore structure and high electrical conductivity, but their non-polar surfaces have weak interactions with LiPSs. Herein, MXene-carbon black/sulfur (Ti3C2Tx-CB/S) composites were prepared and …
Preparation Of 3d Semi-Interpenetrated Polymer Networks Polymer Electrolyte For Lithium Metal Battery,
2021
Sustainable Energy Laboratory, Faculty of Material Science and Chemistry, China University of Geosciences (Wuhan), Wuhan 430074, Hubei, China;
Preparation Of 3d Semi-Interpenetrated Polymer Networks Polymer Electrolyte For Lithium Metal Battery, Yun-Feng Zhang, Jia-Ying Wang, Xiao-Jie Li, Shi-Yu Zhao, Yang He, Shi-Kang Huo, Ya-Ying Wang, Chang Tan
Journal of Electrochemistry
As the next generation high-energy batteries, lithium metal battery has attracted more and more attention due to its highest specific capacity (3860 mA·h·g-1) and the lowest anode potential (-3.04 V versus the standard hydrogen electrode, SHE). However, the safety problem caused by lithium dendrite growth is one of the biggest challenges for the commercialization of lithium metal batteries. Single ion conducting polymer electrolytes, which deliver high lithium ion transference number, represent one of the important strategies to inhibit lithium dendrite growth. However, the poor compatibility with electrodes and low ionic conductivity largely limit their practical application. In the …
A Comparison In Structural Transformation Of Li[NiXCoYMnZ]O2 (X = 0.6, 0.85) Cathode Materials In Lithium-Ion Batteries,
2021
Hefei Gotion High-Tech Power Energy Co., Ltd. Hefei 230012, Anhui, China;
A Comparison In Structural Transformation Of Li[NiXCoYMnZ]O2 (X = 0.6, 0.85) Cathode Materials In Lithium-Ion Batteries, Li-Juan Li, Zhen-Dong Zhu, Juan Dai, Rong-Rong Wang, Wen Peng
Journal of Electrochemistry
In this paper, the phase transformation voltage ranges of two layered oxide ternary cathode materials, namely, Li(Ni0.85Co0.10Mn0.05)O2 (referred to Ni85, presenting high Ni content) and Li(Ni0.6Co0.2Mn0.2)O2 (referred to Ni60, presenting common low Ni content), were classified and determined. The structural differences between high Ni and common low Ni ternary materials were studied in order to understand the structure instability of high nickel material during the charging process. At the same time, the differential capacity (dQ·dV-1) curves of Ni85 and Ni60 positive …
Storage Performance And Mechanism Of Mose2 Nanospheres In Lithium And Magnesium Ion Batteries,
2021
No.38 Research Institute, China Electronics Technology Group Corporation, Hefei 230088, Anhui, China;
Storage Performance And Mechanism Of Mose2 Nanospheres In Lithium And Magnesium Ion Batteries, Yi Peng, Wei Zhang, Fang-Zhen Zuo, Hao-Ying Lv, Kai-Jun Hong
Journal of Electrochemistry
Molybdenum diselenide (MoSe2) is a two-dimensional (2D) transition metal dichalcogenide (TMD) material, attracting wide attention in lithium ion battery (LIB) and exhibiting great potential in next-generation magnesium ion battery (MIB) due to its unique layered structure with fast ion mobility and weak van der Waals interlayer interaction. However, the reported literatures related to MoSe2 mainly focus on the enhancement of performance in LIB without deep storage mechanisms investigations. Meanwhile,the magnesium storage capacity and mechanisms have not been explored. In this work, MoSe2 nanospheres were synthesized via wet chemical route and followed by annealing treatment. When used …
Preparation And Characterization Of Thermoplastic Polyurethane-Based Polymer Electrolyte,
2021
Chemistry and Chemical Engineering College, Anhui University, Hefei 230601, Anhui, China;
Preparation And Characterization Of Thermoplastic Polyurethane-Based Polymer Electrolyte, Li Zhou, Lie Wu, Zhao-Ming Xue
Journal of Electrochemistry
Electrolyte still has to be improved to satisfy the increasingly rigid demands of lithium ion batteries that have higher energy densities. Thermoplastic polyurethane (TPU) has two phase structures of soft segments and hard segments, which can guarantee the electrochemical and physical performances of electrolyte for lithium ion battery. It is now creatively applied to the gel polymer electrolyte matrix of lithium ion batteries. In this paper, a novel polymer membrane based on thermoplastic polyurethane/cellulose acetate (TPU/CA) was prepared by non-solvent induced phase separation (NIPS) method. Further, the TPU/CA blending gel polymer electrolyte (GPE) was prepared by absorbing liquid electrolyte. The …
Dft Study Of NiM@Pt1AuN-M-1 (N=19, 38, 55, 79; M = 1, 6, 13, 19) Core-Shell Orr Catalyst,
2021
1. State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, China;
Dft Study Of NiM@Pt1AuN-M-1 (N=19, 38, 55, 79; M = 1, 6, 13, 19) Core-Shell Orr Catalyst, Wen-Jie Li, Dong-Xu Tian, Hong Du, Xi-Qiang Yan
Journal of Electrochemistry
The slow kinetics of oxygen reduction reaction (ORR) limits the performance of low temperature fuel cells. Thus, it needs to design effective catalysts with low cost. Core-shell clusters (CSNCs) show promising activity because of their size-dependent geometric and electronic effects. The ORR activity trend of Nim@Pt1Aun-m-1(n = 19, 38, 55, 79; m = 1, 6, 13, 19) was studied using the GGA-PBE-PAW methods. The adsorption configurations of *O, *OH and *OOH were optimized and the reaction free energies of four proton electron (H+ + e-) transfer steps …
