The Role Of The 2,7-Dinitroso-1,8-Dihydroxynaphthalene-3,6-Disulfonic Acid Reagent In Determining The Thorium Ion (Iv), 2021 Natiоnal University оf Uzbekistan, Tashkent, Uzbekistan
The Role Of The 2,7-Dinitroso-1,8-Dihydroxynaphthalene-3,6-Disulfonic Acid Reagent In Determining The Thorium Ion (Iv), Nigora Qutlimurotova, Salohiddin Mahmadoliyev, Khabibullo Todjimukhamedov
CHEMISTRY AND CHEMICAL ENGINEERING
The aim is to develop a method for the amperometric determination of thorium (IV) ion with 2,7-dinitroso-1,8-dihydroxynaphthalene-3,6-disulfoxyl reagent. Methods of amperometric determination of thorium by solution of 2,7-dinitrozo-1,8-dihydroxynaphthalene-3,6-disulfonic acid on different acid-base properties of background electrolytes and buffer mixtures are considered. The half-wave potential of new reagent was found by logarithmic analysis equal 0.72 V at pH 2.82, which once again indicates on the irreversibility of the process of electrooxidation of the studied organic reagent in used acid-base medias. The conditions for amperometric titration of thorium are optimized, and the influence of outside accompanying metals on the shape of curves …
A Multifunctional Treatment Process For Combined Sewer Overflow Pollutants And Nutrient Control, 2021 The University of Western Ontario
A Multifunctional Treatment Process For Combined Sewer Overflow Pollutants And Nutrient Control, Tiziana Venditto
Electronic Thesis and Dissertation Repository
Combined sewer overflows (CSOs) contain a highly variable, wide range of contaminants, both in particulate and soluble form, making conventional water treatment processes unable to offer adequate public health protection. To date, no study proposed an efficient and cost-competitive treatment able to remove a broad spectrum of CSO pollutants. This research demonstrated that a chemical pre-treatment, followed by micro-sieve filtration and UV disinfection is an efficient and cost-competitive treatment for CSOs. Pollutant removal was achieved by first adsorbing soluble pollutants on zeolite and powdered activated carbon, and subsequently applying filtration carried out by polymer-enhanced microsieving. Optimal treatment condition, consisting of …
Using Ionic Liquids In Fabrication Of Vo2 For Thermochromic Coatings, 2021 The University of Western Ontario
Using Ionic Liquids In Fabrication Of Vo2 For Thermochromic Coatings, Shidokht Nazari
Electronic Thesis and Dissertation Repository
Energy-efficient or smart windows are an important part of net zero energy housing as excellent candidates for energy conservation. They can control the amount of light and heat passing through them in response to an external stimulus such as heat (thermochromic) or electricity (electrochromic). Vanadium Oxide (VO2) is a potential thermochromic material to provide an automatic reversible semiconductor-metal phase transition from the monoclinic structure to tetragonal at 68 °C. However, there remain major challenges in fabricating desirable VO2-based films to meet the requirements for large-scale implementation. Mainly, the phase transition temperature (Tc) should …
Graphical Design And Analysis Of Mass Exchange Networks Using Composition Driving Forces, 2021 The British University in Egypt
Graphical Design And Analysis Of Mass Exchange Networks Using Composition Driving Forces, Nessren Mohamed Farrag, Dina Ahmed Kamel, Ayat Ossama Ghallab, Mamdouh Ayad Gadalla, Mai Kamal Fouad
Chemical Engineering
Pinch analysis is a methodology for minimizing energy and mass consumption in different industries. It has been widely applied for more efficient processes. This study presents a new graphical-approach to analyze and design Mass Integration (MI) and exchange networks that follows Pinch principles to guarantee maximum mass recovery with minimum losses. This technique uses the composition driving forces in network representation as it rules the mass transfer between streams. The proposed approach can be applied on both existing mass networks as well as new ones. This graphical representation a visual descriptive design tool to describe and explain the details of …
Probing The Role Of Silicates For Corrosion Control In Lead Plumbing, 2021 The University of Western Ontario
Probing The Role Of Silicates For Corrosion Control In Lead Plumbing, Hailey Holmes
Electronic Thesis and Dissertation Repository
Lead service lines and fittings were installed in Canada's drinking water networks until 1986 and currently pose severe health risks. As pipes corrode over decades of use, lead is released into drinking water resulting in dangerous exposure to elevated lead levels. Sodium silicates can be used for corrosion control of lead, however a basic understanding of how they work is lacking. This thesis describes the results of experiments conducted to determine how silicates interact with lead and aluminum in drinking water, using microscopic and spectroscopic techniques. The results show the presence of silicates inhibited Pb2+ carbonates from oxidizing into …
Adsorption And Transport Of Colloids At Interface And In Bulk, 2021 Louisiana State University
Adsorption And Transport Of Colloids At Interface And In Bulk, Jingyun Lee
LSU Doctoral Dissertations
Colloids are suspensions of microscopic insoluble particles dispersed in a continuum phase such as liquid or gas. Colloids are found in our everyday life from food and cosmetic industries to pharmaceutical and biomedical applications. Depending on a global minimum of the free-energy landscape, colloidal suspensions can be classified as two major classes: equilibrium or active colloidal system. This Ph.D dissertation presents strategies to engineer equilibrium self-assembled structures and out-of-equilibrium active matter using various interparticle forces.
First, we introduce the means to promote the equilibrium self-assembled structures driven by adsorption of colloids at interface. Typically, adsorption of colloids at interface is …
Gold-Semiconductor Photocatalysts For Water Treatment Under Visible And Ultraviolet Light, 2021 Louisiana State University and Agricultural and Mechanical College
Gold-Semiconductor Photocatalysts For Water Treatment Under Visible And Ultraviolet Light, Daniel Willis
LSU Doctoral Dissertations
Water scarcity threatens the lives of millions of people worldwide. It is imperative to improve the energy efficiency and affordability of water treatment methods to avoid a looming water-energy crisis. To meet this challenge, I have pursued research on the use of sunlight—our most reliable and abundant source of energy—to drive water treatment through photocatalysis. I explored the literature and found gold-semiconductor materials to hold promise for harvesting sunlight and catalyzing the breakdown of waterborne contaminants. Initially, I designed a novel optical cavity with gold (Au) nanoparticles on a zinc oxide / titania (TiO2) / aluminum film stack …
Fabrication And Characterization Of Electrospun Poly(Acrylonitrile-Co-Methyl Acrylate)/Lignin Nanofibers: Effects Of Lignin Type And Total Polymer Concentration, 2021 University of Dayton
Fabrication And Characterization Of Electrospun Poly(Acrylonitrile-Co-Methyl Acrylate)/Lignin Nanofibers: Effects Of Lignin Type And Total Polymer Concentration, Suchitha Devadas, Saja M. Nabat Al-Ajrash, Donald A. Klosterman, Kenya A. Crosson, Garry S. Crosson, Erick S. Vasquez
Chemical and Materials Engineering Faculty Publications
Lignin macromolecules are potential precursor materials for producing electrospun nanofibers for composite applications. However, little is known about the effect of lignin type and blend ratios with synthetic polymers. This study analyzed blends of poly(acrylonitrile-co-methyl acrylate) (PAN-MA) with two types of commercially available lignin, low sulfonate (LSL) and alkali, kraft lignin (AL), in DMF solvent. The electrospinning and polymer blend solution conditions were optimized to produce thermally stable, smooth lignin-based nanofibers with total polymer content of up to 20 wt % in solution and a 50/50 blend weight ratio. Microscopy studies revealed that AL blends possess good solubility, miscibility, and …
Emulsion Templating Application For Synthesis Of A Porous Zein Biocompatible Oil Adsorbent, 2021 Louisiana State University
Emulsion Templating Application For Synthesis Of A Porous Zein Biocompatible Oil Adsorbent, Nathan Holley
LSU Master's Theses
The recovery of spilled oil from water sources using hydrophobic porous absorbent has gained significant interest due to the ease of implementation, large-scale adaptability, and robust nature of the technique. However, the lack of biodegradability of these synthetic adsorbents has caused concern of further contaminating the environment from the generation of microplastic waste that is known to persist and accumulate in the marine food chain and other ecosystems. To mitigate this potential hazard, a new biocompatible alternative is needed to replace the non-degradable synthetic materials currently used. This thesis presents ZEin-based Low Density porous Absorbent (ZELDA), synthesized using a particle …
Magnetically Induced Demulsification Of Water And Castor Oil Dispersions Stabilized By Fe3o4-Coated Cellulose Nanocrystals, 2021 University of Mississippi
Magnetically Induced Demulsification Of Water And Castor Oil Dispersions Stabilized By Fe3o4-Coated Cellulose Nanocrystals, Mohammad J. Hasan, Frankie A. Petrie, Ashley E. Johnson, Joshua Peltan, Meredith Gannon, Robert T. Busch, Serhiy O. Leontsev, Erick S. Vasquez, Esteban E. Ureña-Benavides
Chemical and Materials Engineering Faculty Publications
Superparamagnetic iron oxide (Fe3O4) nanoparticle (NP) coated cellulose nanocrystals (CNCs) were synthesized and used to prepare emulsions with magnetically controlled stability. Magnetite NPs were deposited onto the surface of wood pulp CNCs (WCNCs) and bacterial CNCs (BCNCs) by a one-step coprecipitation method. The effect of the CNC to Fe3O4 mass ratio (1:1, 1:2, and 1:4) was varied to optimize the colloidal, magnetic and emulsifying properties of the hybrid NPs. TEM images showed that the 1:4 ratios lead to greater coverage of Fe3O4 than lower Fe3O4 loadings (1:1, and 1:2). The CNCs and Fe3O4 appeared to interact via hydrogen bonding between …
Production Of Engineered Carbons From Secondary Waste Streams For Environmental Applications, 2021 The University of Western Ontario
Production Of Engineered Carbons From Secondary Waste Streams For Environmental Applications, Ghazaleh Chegini
Electronic Thesis and Dissertation Repository
Pyrolysis and activation were used in this thesis to produce biochar and activated carbon from industrial digestate and hydrochar materials. In the first part of thesis, digestate derived biochars were obtained by varying the pyrolysis heating rate (10, 80, 100, 200, >1000 °C·min-1) and temperature (300 to 600 °C) to modify their soil-related characteristics (i.e., nutrient leachability, carbon stability, and heavy metal adsorptive capacity). The biochar produced at a temperature of 500 °C and heating rate of 10 °C·min-1 was also activated under using CO2 at 800 °C with different holding times (0.5-2 h). Results indicated …
Recycling Of Cullet, Waste Clay Bricks And Wastes Resulted From Wheat And Sugarcane Cultivations In The Manufacture Of Fired Clay Bricks, 2021 The British University in Egypt
Recycling Of Cullet, Waste Clay Bricks And Wastes Resulted From Wheat And Sugarcane Cultivations In The Manufacture Of Fired Clay Bricks, Mai H. Roushdy
Chemical Engineering
The agriculture wastes are considered as a big environmental problem. The main purpose of this research is to determine the possibility of producing fired clay bricks from a mixture of agriculture wastes in addition to other wastes. The first type of wastes is the cullet while the second type is the wastes is the waste clay bricks (Homra) and the third is an agricultural residue obtained from wheat and sugarcane cultivation. The first step of the experimental work is performing XRF and sieve analysis for raw materials. Brick samples with Cubic shape with dimensions 50 × 50 × 50 mm3 …
Synthesis Of Uio-66 Metal Organic Frameworks, 2021 University of Alabama in Huntsville
Synthesis Of Uio-66 Metal Organic Frameworks, Nicholas Johnston, Larissa Lagria
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
The Effect Of Surface Topography On The Deposition Of Colloids, 2021 University of Alabama in Huntsville
The Effect Of Surface Topography On The Deposition Of Colloids, Mikhail Ramirez
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Microwave-Assisted Natural Gas Conversion To Value-Added Chemicals, 2021 West Virginia University
Microwave-Assisted Natural Gas Conversion To Value-Added Chemicals, Xinwei Bai
Graduate Theses, Dissertations, and Problem Reports
Stranded gas is a raw gas mixture of volatile hydrocarbons where the main composition is methane. The producers flare the stranded gas at the site because the cost of collecting and transporting the gas is higher than the value of the gas itself. To reduce the waste of this natural resource, it is worthwhile to utilize the on-site stranded natural gas as feedstock to produce value-added chemicals without emitting greenhouse gas. Direct natural gas conversion process is more desirable because of lower capital investment. Methane and ethane, the two major components of natural gas, are very stable molecules that usually …
Relating Modified Ergun's Equation To Hindered Settling Correlations, 2021 The University of Akron
Relating Modified Ergun's Equation To Hindered Settling Correlations, Ryan Zahniser
Williams Honors College, Honors Research Projects
Correlations were developed between the Modified Ergun’s and Hindered settling correlations under the condition of dense packing of particles in the bed. As the porosity of the slurry increases, so does the interference between particles in the solution which mimics the behavior of a packed or densely concentrated fluidized bed. The similarity between the two sets of conditions was modeled using mathematical equations to calculate settling velocities and pressure drops by means of the Hindered Settling correlations and Modified Ergun’s equation at porosities ranging from 0.4242 to 0.89. The results showed that a porosity of 0.52 and 0.009 ft particle …
Increasing The Corrosion Protection Of Aisi 1008 Carbon Steel By Surface Treatment With Unmodified And Benzotriazole Modified Sol-Gel Films, 2021 The University of Akron
Increasing The Corrosion Protection Of Aisi 1008 Carbon Steel By Surface Treatment With Unmodified And Benzotriazole Modified Sol-Gel Films, Shane Thomas Kelliher
Williams Honors College, Honors Research Projects
The corrosion performance of sol-gel coated AISI 1008 carbon steel was investigated in 3.5 wt% NaCl solutions of pH 7, 9, and 12 using electrochemical measurements. A corrosion inhibitor, benzotriazole (BTA) was added to the sol-gel mixture and tested as a second, modified sol-gel coating. Sol-gel films adhered evenly to metal samples and were characterized by FTIR spectroscopy. Electrochemical Impedance Spectroscopy (EIS) showed an increase in polarization resistance from blank to sol-gel coated samples (600-18,800,000 ohms). Cyclic polarization (CPP) curves showed positive hysteresis loops for blank and unmodified sol-gel coated samples which increased at high pH following the backward potential …
Specifically Adsorbed Ions In Hematite Flotation, 2021 Michigan Technological University
Specifically Adsorbed Ions In Hematite Flotation, Natalia Parra Alvarez
Dissertations, Master's Theses and Master's Reports
Specifically adsorbed ions, such as calcium and magnesium in iron ore flotation, are ions that can chemically bind with the mineral surfaces and alter the surface properties. Calcium and magnesium are unavoidable in process water and their concentrations are increasing due to water recirculation and reagent additions. These ions are detrimental to the flotation process. Calcium has always been the main focus in research, yet we found that magnesium is more detrimental in flotation due to its smaller atomic size. Starch adsorption in iron ore flotation is key for the effective depression of hematite. It has been determined by flotation, …
Information Architecture For A Chemical Modeling Knowledge Graph, 2021 Virginia Commonwealth University
Information Architecture For A Chemical Modeling Knowledge Graph, Adam R. Luxon
Theses and Dissertations
Machine learning models for chemical property predictions are high dimension design challenges spanning multiple disciplines. Free and open-source software libraries have streamlined the model implementation process, but the design complexity remains. In order better navigate and understand the machine learning design space, model information needs to be organized and contextualized. In this work, instances of chemical property models and their associated parameters were stored in a Neo4j property graph database. Machine learning model instances were created with permutations of dataset, learning algorithm, molecular featurization, data scaling, data splitting, hyperparameters, and hyperparameter optimization techniques. The resulting graph contains over 83,000 nodes …
Molecular-Level Understanding Of Ionic & Electronic Charge Storage Mechanisms In Rechargeable Aluminum Batteries Using Sold-State Nmr, 2021 CUNY City College
Molecular-Level Understanding Of Ionic & Electronic Charge Storage Mechanisms In Rechargeable Aluminum Batteries Using Sold-State Nmr, Ankur Lahanu Jadhav
Dissertations and Theses
Rechargeable aluminum-ion batteries are safe and low-cost alternatives to traditional lithium-ion batteries due to the high volumetric capacity (8040 mAh/cm3) of aluminum. However, very few electrode materials have shown reversible aluminum ion intercalation. Intercalation Al3+ ions in these structures leads to poor capacity retention, mainly due to slow solid-state diffusion of the highly charged tri-valent aluminum ions within these crystalline structures. In 2015, aluminum ions were shown to reversibly intercalate/de-intercalate into the Chevrel Mo6S8 phase, though the intercalation mechanism is not well understood. Alternatively, molecular chloroaluminate ions within the ionic liquid electrolyte have also …