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Full-Text Articles in Chemical Engineering

Comparison Of Pretreatment Methods For The Production Of Ethanol, Emily Schulte Apr 2020

Comparison Of Pretreatment Methods For The Production Of Ethanol, Emily Schulte

Honors Theses

Bioethanol provides a great alternative to regular ethanol sources because it uses secondary substrates that are byproducts of other industries, rather than substrates that compete with food products. The technology is available for industrial bioethanol production, but the production costs just aren’t competitive enough with traditional ethanol production. The goal of this project was not to prepare a proposal for a bio-ethanol plant with all of the associated costs and financial calculations, but rather to provide a direct comparison of two pretreatment methods to highlight which factors could make one method less costly than the other. Pretreatment is a critical …


Development Of A Flexible Printed Paper-Based Battery, Justone Crosby Apr 2020

Development Of A Flexible Printed Paper-Based Battery, Justone Crosby

Honors Theses

Market demand for flexible electronics continues to grow, which, in turn, increases the demand for flexible energy storage devices. There are several types of energy storage devices available, including the alkaline (Zn-MnO2) battery, which is the subject of this project. This project's objective was to develop a flexible, printed paper-based battery, which may be a sustainable solution to the increasing market demand. This device is low-cost and can be manufactured commercially using a scalable process.

The proposed device is an alkaline flexible cell, whose components can be printed onto paper. This alkaline system includes a zinc-based negative electrode …


Steam Valve Thermo-Performance Analysis, Benjamin Evans Apr 2020

Steam Valve Thermo-Performance Analysis, Benjamin Evans

Honors Theses

Steam leaks occur in aging power systems due to heat energy loss in the valves of that system. A model was developed to determine the amount of heat energy lost in Donald C. Cook Nuclear Power Plant’s steam pipe valve system. Several methods were used to determine the mass flow rate and used to model the system in PEPSE. The PEPSE model determined the estimated energy that was lost due to seal leakage and general valve degradation. A program was created for use of plant employees to easily calculate the lost generation in MWe due to these leaks using the …


Steam Valve Thermo-Performance Analysis, Turner Slaughter Apr 2020

Steam Valve Thermo-Performance Analysis, Turner Slaughter

Honors Theses

Steam leaks occur in aging power systems due to heat energy loss in the valves of that system. A model was developed and programmed using Excel to determine the amount of heat energy lost in an aging power plant steam pipe valve system. This model was tested using data from an existing model called PEPSE. The PEPSE model determined the estimated energy that was lost due to seal leakage and general valve degradation. The energy from the steam was quantified using downstream temperature measurement data that was processed with multiple calculation methods to ensure accuracy in the model. The excel …


Paper Recycling Fiber Recapture, Abigail Cortright Apr 2020

Paper Recycling Fiber Recapture, Abigail Cortright

Honors Theses

The goal of the Yoda Chemical Company Paper Recycling Fiber Recapture project and subsequent report was to identify and recommend plant optimization opportunities associated with the potential recovery of five waste streams. Additionally, an analysis of the upgrade’s design was completed in order to determine the economic viability of fiber recapture. Beginning the analysis, the five waste streams were identified and analyzed. The waste streams include the top liner, back liner, and filler liner primary cleaner rejects on the K1 machine, the common rejects from under the K3 paper machine, and the tertiary cleaner rejects from stock preparation.

Two different …


Inducing Increased Bioplastic Production In R. Palustris Cga009, Cameron Gilley, Dylan Hoppner, Brandi J. Brown Apr 2020

Inducing Increased Bioplastic Production In R. Palustris Cga009, Cameron Gilley, Dylan Hoppner, Brandi J. Brown

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

PHA’s (polyhydroxyalkanoates) are important bio polymers in different industries such as petroleum, medicine, and nano technology. In the microorganisms in which they are produced, they serve as an energy storage material by storing both carbon and usable electrons. This is useful in environments where the organisms are nutrient starved. PHA’s have a practical use especially in the medical field as bio-plastics because they are biodegradable and bio-compatible. Rhodopseudomonas. palustris, a common soil bacterium, is notable for its uncommon metabolic flexibility. Its diverse metabolism means that it can fix CO 2 and grow on many lignin based monomers in both aerobic …


Internals In Gas-Liquid Systems, Sai Sankar Ganesan Apr 2020

Internals In Gas-Liquid Systems, Sai Sankar Ganesan

LSU Doctoral Dissertations

The objective of this study is to model gas-liquid contact and separation problems (using Euler-Euler based Computational Fluid Dynamic (CFD) models) at different scales. We have explored process intensive solutions, design optimizations by introducing internals in these gas-liquid operations.

A 500L pilot plant scale and a 7000L industrial scale novel down-flow bubble column problems were modeled. Methodologies used to overcome challenges on large-bubble micro-bubble dynamics are discussed and the resulting fluid dynamic solutions were studied. These solutions were further modified and tailored toward intensification, by exploring horizontal plate internals. We then modeled mass transfer and reaction kinetics on this system …


Benchmark Temperature Microcontroller For Process Dynamics And Control, Junho Park, Ronald Abraham Martin, Jeffrey Kelly, John Hedengren Apr 2020

Benchmark Temperature Microcontroller For Process Dynamics And Control, Junho Park, Ronald Abraham Martin, Jeffrey Kelly, John Hedengren

Faculty Publications

Standard benchmarks are important repositories to establish comparisons between competing model and control methods, especially when a new method is proposed. This paper presents details of an Arduino micro-controller temperature control lab as a benchmark for modeling and control methods. As opposed to simulation studies, a physical benchmark considers real process characteristics such as the requirement to meet a cycle time, discrete sampling intervals, communication overhead with the process, and model mismatch. An example case study of the benchmark is quantifying an optimization approach for a PID controller with 5.4% improved performance. A multivariate example shows the quantified performance improvement …


Synthesis And Characterization Of Pvp Based Catalysts For Selected Application In Catalysis, Hany A. Elazab, Mohamed N. Ayad, Mohamed M. Hammam, M. A. Radwan, M. A. Sadek Apr 2020

Synthesis And Characterization Of Pvp Based Catalysts For Selected Application In Catalysis, Hany A. Elazab, Mohamed N. Ayad, Mohamed M. Hammam, M. A. Radwan, M. A. Sadek

Chemical Engineering

This research aims to study the catalyst activity in specific reactions and the characteristics of the catalyst in order to optimize its performance. This research investigates PVP based catalysts and their properties and applications. PVP was prepared in combination with different metal oxides in order to be tested for different catalytic applications including dye removal. Methyl orange was used as a dye and different concentrations were tested against different metallic ions in order to optimize the catalyst for being used in dye removal applications. Spectrophotometer was used to calculate the concentration of the dye before and after catalyst exposure and …


Hysteresis Effects And Roughness Suppression Efficacy Of Polyethylenimine Additive In Cu Electrodeposition In Ethaline, Nora A. Shaheen, Ijjada Mahesh, Rohan Akolkar Apr 2020

Hysteresis Effects And Roughness Suppression Efficacy Of Polyethylenimine Additive In Cu Electrodeposition In Ethaline, Nora A. Shaheen, Ijjada Mahesh, Rohan Akolkar

Faculty Scholarship

Deep eutectic solvents (DES) are environmentally-friendly electrolytes that are gaining interest for electrodeposition and energy storage applications. In these applications, metal electrodeposits with smooth, nondendritic morphology are desired and thus effective strategies for suppressing roughness evolution are critically needed. A commonly employed and rather effective strategy for suppressing roughness evolution in metal electrodeposition is the use of electrolyte additives; however, the availability of such additives in DES electrolytes is limited and so is the understanding of the mechanisms through which additives suppress roughness amplification in DES media. In the present contribution, we demonstrate that polyethylenimine (PEI) is an effective electrolyte …


Mitigating Safety Concerns And Profit/Production Losses For Chemical Process Control Systems Under Cyberattacks Via Design/Control Methods, Helen Durand, Matthew Wegener Apr 2020

Mitigating Safety Concerns And Profit/Production Losses For Chemical Process Control Systems Under Cyberattacks Via Design/Control Methods, Helen Durand, Matthew Wegener

Chemical Engineering and Materials Science Faculty Research Publications

One of the challenges for chemical processes today, from a safety and profit standpoint, is the potential that cyberattacks could be performed on components of process control systems. Safety issues could be catastrophic; however, because the nonlinear systems definition of a cyberattack has similarities to a nonlinear systems definition of faults, many processes have already been instrumented to handle various problematic input conditions. Also challenging is the question of how to design a system that is resilient to attacks attempting to impact the production volumes or profits of a company. In this work, we explore a process/equipment design framework for …


Zeolite Monolith Compositions And Methods For The Catalytic Cracking Of Alkanes, Ali A. Rownaghi, Xin Li, Fateme Rezaei Apr 2020

Zeolite Monolith Compositions And Methods For The Catalytic Cracking Of Alkanes, Ali A. Rownaghi, Xin Li, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Porous zeolite monolith compositions for the catalytic cracking of alkanes. The compositions may be prepared layer by layer using a 3D printer such that the compositions comprise a plurality of micropores and a plurality of mesopores and may be characterized by macro-meso-microporosity.


Modeling Unconventional Water Production In The Northeast Elm Coulee Field, Bakken Formation, Jan Branning Apr 2020

Modeling Unconventional Water Production In The Northeast Elm Coulee Field, Bakken Formation, Jan Branning

Graduate Theses & Non-Theses

Wells within the Northeast (NE) Elm Coulee produce significantly higher water cuts than wells within Elm Coulee Proper. The purpose of this work was to identify the source of produced water in the NE Elm Coulee. An area within the NE Elm Coulee was selected for a numerical flow simulation analysis, and a total of three models of the project area were constructed by isolating production mechanisms to determine the source of produced water in the NE Elm Coulee. A Separate Tank model was constructed to determine if the source of the produced water was matrix water saturation in the …


Effects Of Collision Damage On The Ultimate Strength Of Fpso Vessels, Muhammad Zubair Muis Alie, Dian Ramasari, Taufiqur Rachman, Ristiyanto Adiputra Apr 2020

Effects Of Collision Damage On The Ultimate Strength Of Fpso Vessels, Muhammad Zubair Muis Alie, Dian Ramasari, Taufiqur Rachman, Ristiyanto Adiputra

Makara Journal of Technology

Floating production storage offloading (FPSO) vessels are movable offshore structures. These structures are designed with large dimensions, and their decks are loaded with several types of equipment. During collision damage, the hull and deck parts loaded with equipment are severely affected. Therefore, the ultimate strength of FPSO vessels should be thoroughly checked and evaluated. The objective of the present study is to analyze the ultimate strength of FPSO vessels against collision damage characterized by hogging and sagging under longitudinal bending. The cross section of an FPSO vessel is modeled with elements composed of stiffened and unstiffened plates. The vessel length …


Synthesis Of Epoxy Monoethanolamide From Bauhinia Monandra Seed Oil, Adewale Adewuyi, Rotimi A. Oderinde Apr 2020

Synthesis Of Epoxy Monoethanolamide From Bauhinia Monandra Seed Oil, Adewale Adewuyi, Rotimi A. Oderinde

Makara Journal of Technology

In this study, we synthesized epoxidised monoethanolamide (EMA) from Bauhinia monandra seed oil (BMO) via a simple reaction route. In this process, BMO was transesterified to obtain a mixture of methyl esters, which was subjected to a urea adduct complexation reaction. The unsaturated methyl esters (BME) from the urea adduct complexation reaction were then epoxidised using performic acid produced in situ in a one-pot reaction system. The epoxidised methyl esters were converted to EMA by reacting them with monoethanolamine (1:10). The progression of the reaction was monitored using Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, and the …


Ethylene Carbonate And Polyethylene Glycol As Efficient Plasticizers In Cmc-Pva-Nh4no3-Based Polymer Electrolyte, Noor Saadiah Mohd Ali, Yuki Nagao, Ahmad Salihin Samsudin Apr 2020

Ethylene Carbonate And Polyethylene Glycol As Efficient Plasticizers In Cmc-Pva-Nh4no3-Based Polymer Electrolyte, Noor Saadiah Mohd Ali, Yuki Nagao, Ahmad Salihin Samsudin

Makara Journal of Technology

This study investigated the influence of plasticizers (polyethylene glycol [PEG] and ethylene carbonate [EC]) on the ionic conduction of CMC-PVA-NH4NO3. Blended biopolymer electrolytes (BBEs) based on carboxymethyl cellulose–polyvinyl alcohol (CMC-PVA) doped with ammonium nitrate (NH4NO3) were obtained via casting solution technique incorporated with PEG and EC, which acted as plasticizers. Electrical impedance spectroscopy (EIS) was conducted to evaluate the effect of plasticization on the ionic conduction properties. The ionic conductivity improved from 1.70 × 10−3 S/cm for un-plasticized BBEs to 3.92 × 10−3 S/cm for plasticized BBEs with EC and 3.00 × 10−3 S/cm for plasticized BBEs with PEG. The …


Liquefaction Potential Analysis Based On Nonlinear Ground Response On The Coastline Of Bengkulu City, Indonesia, Lindung Zalbuin Mase Apr 2020

Liquefaction Potential Analysis Based On Nonlinear Ground Response On The Coastline Of Bengkulu City, Indonesia, Lindung Zalbuin Mase

Makara Journal of Technology

This paper presents the study of the seismic response and liquefaction potential of the coastal area of Bengkulu City during the September 2007 Sumatra earthquake. The study is conducted by collecting site investigation data (standard penetration test) and applying input motion to observe soil response. Synthetic ground motion is generated by considering the important aspects of earthquakes, including focal depth, epicenter, earthquake source, and site classification. The synthetized ground motion is then used as the input motion in the seismic response analysis. The results of this analysis are spectral acceleration and peak ground acceleration at each depth. The resulting spectral …


Comparison Of Phytoremediation And Filtration For Diamond-Mine-Tailings Water Treatment, M. Hafidhuddin Noor, Mijani Rahman, Akhmad Gazali, Nia Kania, Aulia Rahma, Erdina L.A. Rampun, Amalia E. Pratiwi, Muthia Elma Apr 2020

Comparison Of Phytoremediation And Filtration For Diamond-Mine-Tailings Water Treatment, M. Hafidhuddin Noor, Mijani Rahman, Akhmad Gazali, Nia Kania, Aulia Rahma, Erdina L.A. Rampun, Amalia E. Pratiwi, Muthia Elma

Makara Journal of Technology

The water pollution caused by diamond mine activities can kill aquatic life. In this work, we used phytoremediation and filtration to treat pond water polluted by the tailings of a diamond mine located in South Kalimantan, Indonesia. Einchhornia crassipes (water hyacinth) was utilized as the biomass for the phytoremediation process. Gravel (10–15 mm) and sand (0.1–1 mm) were used as filter media in the simple filtration setup, using an up-flow system (bottom to top). In the experiment, 16 L of diamond tailing water was poured into five phytoremediation reactors (each 60 L in volume), which were then tested over seven …


Fabrication Of Composite Membranes For Solar-Thermal Desalination, Andrew Mason, Mahdi Mohammadighaleni, Siamak Nejati Apr 2020

Fabrication Of Composite Membranes For Solar-Thermal Desalination, Andrew Mason, Mahdi Mohammadighaleni, Siamak Nejati

UCARE: Research Products

With rising human populations, the demand for freshwater is an ever-growing problem. One emerging technology to combat this problem is membrane distillation (MD). MD has several advantages for water desalination such as:

•100% rejection of solute (salt, heavy metals, etc.) •Mergeable with other affordable energy sources (solar heat, electric resistance, etc.)

However, at the moment the specific energy consumption (SEC) of MD is very high due to low water production rates and large energy inputs to heat water. In a solar-assisted design for MD, the high cost of solar collectors (~$200/m2) inhibits low cost of water production in comparison to …


The Development Of Polymer Constructs For Adipose Tissue Engineering Applications, Kendall Murphy Apr 2020

The Development Of Polymer Constructs For Adipose Tissue Engineering Applications, Kendall Murphy

Theses and Dissertations

The adipose tissue functions as the body’s main energy reservoir and plays a central role in maintaining whole body energy homeostasis. The ability to modulate this tissue’s inherent endocrine and metabolic functions has promising implications in treating disease associated with adipose tissue dysfunction. This work revolves around two diseases where adipose tissue inflammation and metabolic dysfunction drive the disease, obesity and cachexia. Both diseases impact a significant population of U.S. adults and substantially reduce patient quality of life.

In this study, we first demonstrate the use of novel therapeutic platforms engineered to specifically target adipose tissue inflammation and lipid catabolism …


Influence Of Coordination Environment On Catalyst Structure And Function For Co2 Hydrogenation And Ethane Partial Oxidation, Juan D. Jimenez Apr 2020

Influence Of Coordination Environment On Catalyst Structure And Function For Co2 Hydrogenation And Ethane Partial Oxidation, Juan D. Jimenez

Theses and Dissertations

In this work, we set out to establish strong structure/activity relationships for various catalytic compositions and reactions. Through in situ spectroscopic approaches, specifically DRIFTS, Raman XPS, and XAFS, we were able to discern the reactive species in CO2 hydrogenation over highly active cobalt nanostructures, the relevant ensemble size and composition of single site catalysts for CO2 hydrogenation, and active vibrational modes of mixed oxide catalysts for ethane partial oxidation (EPO).

First, we illustrate how tailoring surface orientations of Co3O4 catalysts on the nanoscale results in control over catalytic performance via the preferential formation of active …


Oxidized Phospholipid Regulation Of Chronic Inflammation In Endothelial Cells, Cameron Scott Brutsche Apr 2020

Oxidized Phospholipid Regulation Of Chronic Inflammation In Endothelial Cells, Cameron Scott Brutsche

Masters Theses

Atherosclerosis, the primary cause of Coronary Heart Disease (CHD), has become one of the top causes of death in the world. As low-density lipoprotein (LDL) particles become trapped and oxidized inside arterial walls, the primary oxidation products of 1-palmitoyl-2-arachidonyl-sn-glycerol-3-phosphatidylcholine (PAPC) induce the binding of monocytes which can potentially lead to fatty plaque build ups. A fragment of one of these oxidation products, OxPAPC, has previously been studied and can act as standard for testing new phospholipids and how they affect protein expression levels. The central hypothesis of this study was that three newly studied classes of oxidized fatty …


Production Of Renewable Hydrocarbon Fuel Via Titanium Oxide-Alumina (Tio2-Al2o3) Catalytic Deoxygenation Reaction, Xian Yih Ooi Apr 2020

Production Of Renewable Hydrocarbon Fuel Via Titanium Oxide-Alumina (Tio2-Al2o3) Catalytic Deoxygenation Reaction, Xian Yih Ooi

Student Works (2020-2029)

The renewable hydrocarbon-like biofuel from biomass is crucial to substitute fossil fuel. Catalytic deoxygenation is a biofuel upgrading process to eliminate the high oxygen content in biofuel which will lead to corrosion, instability and lower heating value problems. The choice of support is significant to provide the maximum acid strength for the hydrogenolysis of C-O bonds. Al2O3 supported catalyst has drawn attention due to the high acidity. However, the high acidity leads to coke deposition, unstable and deactivation of the catalyst. Thus, it is important to develop methods to improve catalyst performance, reduce catalyst coking and enhance catalyst lifetime. Recently, …


Poly(Vinyl Alcohol)/Α-Chitin/Nanocellulose Composites Developed From Oil Palm Empty Fruit Bunch (Opefb) For Removal Of Cationic Dyes, Chun Fah Mok Apr 2020

Poly(Vinyl Alcohol)/Α-Chitin/Nanocellulose Composites Developed From Oil Palm Empty Fruit Bunch (Opefb) For Removal Of Cationic Dyes, Chun Fah Mok

Student Works (2020-2029)

In search of an eco-friendly polymeric adsorbent for dye effluent treatment application, poly(vinyl alcohol) (PVA)/chitin/nanocellulose composites were synthesized. The composites were reinforced by oil palm empty fruit bunch fibers (OPEFB)-derived nanocrystalline cellulose (NCC). With addition of 1 wt.% NCC, a maximum improvement of 57.64% and 50.66% in tensile strength and Young’s Modulus were achieved, respectively. However, the PVA-based composites exhibited low resistance in aqueous medium. Hence, maleic acid (MA) was incorporated, in view of modifying PVA-based composites through cross-linking reactions. The effect of varying chitin content (10 wt.%-30 wt.%) and MA content (10%-50% based on total solid content of composite) …


Ionic Conductivity And Electrochemical Properties Of Alginate–Nn4no3-Based Biopolymer Electrolytes For Edlc Application, Norfatihah Binti Mazuki, Nur Muhitul Jalilah Rasali, Bouchta Sahraoui, Ahmad Salihin Samsudin Apr 2020

Ionic Conductivity And Electrochemical Properties Of Alginate–Nn4no3-Based Biopolymer Electrolytes For Edlc Application, Norfatihah Binti Mazuki, Nur Muhitul Jalilah Rasali, Bouchta Sahraoui, Ahmad Salihin Samsudin

Makara Journal of Technology

In this work, alginate doped with various contents of ammonium nitrate (NH4NO3) as a solid biopolymer electrolyte (SBE) was prepared via casting by using distilled water as a solvent. Impedance studies on alginate–NH4NO3 SBE films were conducted via impedance spectroscopy. The lowest bulk resistance (Rb) showed that the maximum ionic conductivity of the sample containing 25 wt.% NH4NO3 at ambient temperature (303 K) was 5.56 × 10−5 S cm−1. The temperature dependence of ionic conductivity was evaluated, and results confirmed that electrolytes followed an Arrhenius behavior. The highest conducting sample was fabricated into an electrical double-layer capacitor and characterized in …


Current Status Of Hydrothermal Treatment For Energy And Material Recovery Toward A Sustainable Post-Consumer Material Cycle, Baskoro Lokahita, Muhammad Aziz, Fumitake Takahashi Apr 2020

Current Status Of Hydrothermal Treatment For Energy And Material Recovery Toward A Sustainable Post-Consumer Material Cycle, Baskoro Lokahita, Muhammad Aziz, Fumitake Takahashi

Makara Journal of Technology

The demand for energy-efficient and environmentally friendly municipal solid waste (MSW) processing has increased in developing countries. The thermochemical process offers a fast and reliable solution to reutilize or reduce the volume of MSW. Hydrothermal treatment is a novel MSW treatment technology that is compatible with high-moisture-content feedstock. It involves the thermal degradation of MSW in pressurized water or steam, which promotes the disintegration of cellulosic and polymer materials. Recent advances have shown effective MSW conversion into homogenous solid hydrochar with higher energy density. Alkali and chlorine content, which causes issues in combustors, was successfully removed due to the washing …


Evaluation Of The Embedded Environmental Impacts Of The Sanitary Sewer System Using Life Cycle Assessment, Kimberly Law Apr 2020

Evaluation Of The Embedded Environmental Impacts Of The Sanitary Sewer System Using Life Cycle Assessment, Kimberly Law

UCARE: Research Products

This study identifies the overall impact that the installation and construction phase of sanitary sewer systems have on the environment. Construction data on sanitary sewer systems from small Nebraska communities was collected and compared to the operating phase of the sanitary sewer. The operating phase is the energy required for the lift station. Analyzing sanitary sewers during their entire life cycle involved the raw materials, infrastructure construction, installation, operation of the system, and maintenance.

Wastewater treatment systems are meant to reduce the negative impact that humans have on the environment. The purpose of the system is to treat and disinfect …


Multi-Scale Modeling For Transport Study Inside Porous Layers Of Polymer Electrolyte Membrane Fuel Cell Using Direct Numerical Simulation, Pongsarun Satjaritanun Apr 2020

Multi-Scale Modeling For Transport Study Inside Porous Layers Of Polymer Electrolyte Membrane Fuel Cell Using Direct Numerical Simulation, Pongsarun Satjaritanun

Theses and Dissertations

The direct modeling-based Lattice Boltzmann Agglomeration Method (LBAM) is used to explore the electrochemical kinetics and multi-scalar/multi-physics transport inside the detailed structure of the porous and catalyst layers inside polymer electrolyte membrane fuel cells (PEMFCs). The complete structure of the samples is obtained by both micro- and nano- X-ray computed tomography (CT). LBAM is able to predict the electrochemical kinetics in the nanoscale catalyst layer and investigate the electrochemical variables during cell operation. This work shows success in integrating the lattice elements into an agglomerate structure in the catalyst layer (CL). The predictions using LBAM were compared and validated with …


Tunable Luminescence Of Rare Earth Doped Nanophosphors Via Adaptive Optical Properties Of Transition Metals, Pragathi Darapaneni Mar 2020

Tunable Luminescence Of Rare Earth Doped Nanophosphors Via Adaptive Optical Properties Of Transition Metals, Pragathi Darapaneni

LSU Doctoral Dissertations

Over the past decades, the development of light-emitting diodes (LEDs) to produce a wide range of wavelengths has revolutionized the solid-state lighting industry due to their higher energy efficiency and operational lifetimes. These LEDs employ rare earth (RE) doped phosphors due to their stable emission wavelengths which can be amplified when sensitized by other RE dopants (Yb, Ce) or shell layer passivation. However, there has been a push to replace the RE elements in LEDs due to increased socioeconomic issues. One proposed alternative, transition metal (TM) dopants, is typically avoided due to their susceptibility to the local crystal environment resulting …


Research Of Increasing The Reactivity Cotton Cellulose Intended For Chemistry, R.S. Sayfutdinov, U.D. Mukhitdinov, N.M. Eshpulatov Mar 2020

Research Of Increasing The Reactivity Cotton Cellulose Intended For Chemistry, R.S. Sayfutdinov, U.D. Mukhitdinov, N.M. Eshpulatov

Technical science and innovation

The reactivity of cotton pulp during chemical processing is significantly lower compared to celluloses obtained from other cellulose-containing plants. Increasing the reactivity of cotton cellulose improves the quality of the products based on it, and also increases labor productivity.

The aim of this work is to study the possibility of replacing wood pulp imported from foreign countries with domestic cotton cellulose by increasing the reactivity of cotton cellulose for chemical processing, improving the quality of the resulting product and increasing the reaction rate.

In this work, we used methods for determining the composition and structure of cotton cellulose samples. The …