Chemical Engineering Commons^™

Fabrication Of Thin-Film Composite, Reverse-Osmosis Membranes With Polyethylenimine Modifications For Enhancing Membrane Fouling Resistance, Stephanie N. Hamilton

Master's Theses

Increasing water reuse opportunities for communities has become increasingly important as access to clean water is becoming more scarce. Reverse Osmosis (RO) is an advanced treatment technology used in water recycling wastewater for potable reuse applications. RO is a promising technology; however, the membranes have limitations including their high energy demand and their susceptibility to membrane fouling. The main objective of this study was to develop a reproducible method for the fabrication of RO membranes with enhanced flux and reduced susceptibility to fouling. Literature contains numerous publications on fabrication of thin film composite (TFC) RO membranes with high performance. However, …

Phase Transitions And Photoluminescent Properties Of Anion-Engineered Y2o3, Maharram Jabrayilov

LSU Master's Theses

Rare earth doped metal oxides are widely employed as phosphor materials for white light LEDs (w-LEDs). The aim of this work is to engineer anionic sites of metal oxides, specifically, Y₂O₃, to investigate structural and luminescent properties relationships and energy transfer mechanisms between rare earth sensitizer and activator ions in different hosts.

A low temperature two-step hydrothermal/combustion method was employed to incorporate sulfate ions into Y₂O₃. Furthermore, annealing at 600 °C under H₂/N₂ was employed to convert Y₂O₂SO₄ to Y₂O₂S. …

Application Of The Core Shell Model For Strengthening Polymer Filament Interfaces, Yu-Chung Lin, Aniket Raut, Yiwei Fang, Yifan Yin, David Sprouster, Tai-De Li, Guillaume Freychet, Mikhail Zhernenkov, Steve Nitodas, Jonathan Sokolov, Yuval Shmueli, Miriam Rafailovich

Advanced Science Research Center

While surface segregation has been intensively studied in thin films, relatively little has been investigated in filament geometries. In contrast to thin films, the filament surface forms a continuum, with interactions both at the free air and internal filament interface, which makes it difficult to achieve an equilibrium configuration. This asymmetry has become particularly apparent with the increasing use of additive manufacturing where entire structures are constructed via layered deposition of filamentous layers from a moving thermal nozzle. In addition, this process is highly non-equilibrated with poor thermal retention and is responsible for insufficient filament–filament interfacial fusion and internal pore …

Electrochemical Syntheses Of Nanomaterials And Small Molecules For Electrolytic Hydrogen Production, Jia-Qi Wei, Xiao-Dong Chen, Shu-Zhou Li

Journal of Electrochemistry

Hydrogen is a clean, efficient, renewable energy resource and the most promising alternative to fossil fuels for future carbon-neutral energy supply. Therefore, sustainable hydrogen production is highly attractive and urgently demanded, especially via water electrolysis that has clean, abundant precursors and zero emission. However, current water electrolysis is hindered by the sluggish kinetics and low cost/energy efficiency of both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In this regard, electrochemical synthesis offers prospects to raise the efficiency and benefit of water electrolysis by fabricating advanced electrocatalysts and providing more efficient/value-adding co-electrolysis alternatives. It is an eco-friendly and facile …

Alkaline Seawater Electrolysis At Industrial Level:Recent Progress And Perspective, Tao Zhang, Yi-Pu Liu, Qi-Tong Ye, Hong-Jin Fan

Journal of Electrochemistry

Industrial hydrogen generation through water splitting, powered by renewable energy such as solar, wind and marine, paves a potential way for energy and environment sustainability. However, state-of-the-art electrolysis using high purity water as hydrogen source at an industrial level would bring about crisis of freshwater resource. Seawater splitting provides a practical path to solve potable water shortage, but still faces great challenges for large-scale industrial operation. Here we summarize recent developments in seawater splitting, covering general mechanisms, design criteria for electrodes, and industrial electrolyzer for direct seawater splitting. Multi-objective optimization methods to address the key challenges of active sites, reaction …

A Self-Supported Ru-Cu3P Catalyst Toward Alkaline Hydrogen Evolution, Zi-Xuan Wan, Chao-Hui Wang, Xiong-Wu Kang

Journal of Electrochemistry

Transition metal phosphide (TMP) is a kind of effective catalysts toward hydrogen evolution reaction (HER) in alkaline electrolytes. However, the performance of TMP catalysts is strongly limited by water splitting. In this work, we developed a method to prepare a copper foam (CF) supported Ru-doped Cu₃P catalyst (Ru-Cu₃P/CF) by a consecutive growth of Cu(OH)₂ nanoarrays, soaking in RuCl₃ solution and phosphorization. A large surface area was obtained by the self-supported catalysts with the appropriative Ru doping. As an excellent HER catalyst, it exhibited a low overpotential of 95.6 mV at a current density of …

Catalytic Effect Of Disordered Ru-O Configurations For Electrochemical Hydrogen Evolution, Xue Sun, Ya-Jie Song, Ren-Long Li, Jia-Jun Wang

Journal of Electrochemistry

Phase engineering is considered as an effective method for modulating the electronic structure and catalytic activity of catalysts. The disordered conformation of amorphous materials allows flexible reforming of the surface electronic structure, showing their attractiveness as catalysts for hydrogen evolution reaction (HER). Herein, we designed and developed an amorphous ruthenium dioxide (a-RuO₂) catalyst with a disordered Ru-O configuration. The conformational relationship between Ru-O ordering and HER performance is established by combining advanced electron microscopic techniques with detailed electrochemical tests. Specifically, the disordered Ru-O coordination significantly enhanced the HER catalytic activity in both acidic and alkaline media, ultimately leading …

Alkaline Water Electrolysis For Efficient Hydrogen Production, Wen-Fu Xie, Ming-Fei Shao

Journal of Electrochemistry

Hydrogen production from water electrolysis is a sustainable and environmentally benign strategy in comparison with fossil fuel-based hydrogen. However, this promising technique suffers from the high energy consumption and unsatisfactory cost due to the sluggish kinetics of both half reaction and inferior stability of electrocatalysts. To address this challenge, herein, we present a timely and comprehensive review on advances in alkaline water electrolysis that is already commercialized for large scale hydrogen production. The design principles and strategies with aiming to promote the performance of hydrogen generation are discussed from the view of electrocatalyst, electrode, reaction and system. The challenges and …

Method For Routine Density Measurement Of Sublimating Solid Carbon Dioxide (Dry Ice) For Cold-Chain Quality Control, Kimberly Hafner, Bruce A. Welt, William Pelletier

Journal of Applied Packaging Research

With recent development of vaccines and biologics, interest in dry ice for cold chain shipping has increased. However, understanding of how dry ice properties relate to performance is not well understood. This study introduces a simple method for measuring a key property of dry ice that has been shown to correlate to performance. The method involves a variant of the water displacement method for determining volume, where dense solid particles are used in place of water for volume determination. Three particle types (sieved sand, glass beads, and stainless-steel shot) were tested for suitability with the particle displacement method. Items of …

Electrophilic Aldehyde 4-Hydroxy-2-Nonenal Mediated Signaling And Mitochondrial Dysfunction, Sudha Sharma, Papori Sharma, Tara Bailey, Susmita Bhattarai, Utsab Subedi, Chloe Miller, Hosne Ara, Srivatsan Kidambi, Hong Sun, Manikandan Panchatcharam, Sumitra Miriyala

Department of Chemical and Biomolecular Engineering: Faculty Publications

Reactive oxygen species (ROS), a by-product of aerobic life, are highly reactive molecules with unpaired electrons. The excess of ROS leads to oxidative stress, instigating the peroxidation of polyunsaturated fatty acids (PUFA) in the lipid membrane through a free radical chain reaction and the formation of the most bioactive aldehyde, known as 4-hydroxynonenal (4-HNE). 4-HNE functions as a signaling molecule and toxic product and acts mainly by forming covalent adducts with nucleophilic functional groups in proteins, nucleic acids, and lipids. The mitochondria have been implicated as a site for 4-HNE generation and adduction. Several studies clarified how 4-HNE affects the …

Film-Terminated Fibrillar Microstructures With Improved Adhesion On Skin-Like Surfaces, Gabriela Moreira Lana, Xuan Zhang, Christian Müller, René Hensel, Eduard Arzt

Chemical and Biochemical Engineering Faculty Research & Creative Works

Adhesives for interaction with human skin and tissues are needed for multiple applications. Micropatterned dry adhesives are potential candidates, allowing for a conformal contact and glue-free adhesion based on van der Waals interactions. In this study, we investigate the superior adhesion of film-terminated fibrillar microstructures (fibril diameter, 60 μm; aspect ratio, 3) in contact with surfaces of skin-like roughness (Rz 50 μm). Adhesion decays only moderately with increasing roughness, in contrast to unstructured samples. Sinusoidal model surfaces adhere when their wavelengths exceed about four fibril diameters. The film-terminated microstructure exhibits a saturation of the compressive force during application, implying a …

Insight Into Nano-Chemical Enhanced Oil Recovery From Carbonate Reservoirs Using Environmentally Friendly Nanomaterials, Ali Ahmadi, Abbas Khaksar Manshad, Jagar A. Ali, Stefan Iglauer, S. Mohammad Sajadi, Alireza Keshavarz, Amir H. Mohammadi

Research outputs 2022 to 2026

The use of nanoparticles (NPs) in enhanced oil recovery (EOR) processes is very effective in reducing the interfacial tension (IFT) and surface tension (ST) and altering the wettability of reservoir rocks. The main purpose of this study was to use the newly synthesized nanocomposites (KCl / SiO₂ / Xanthan NCs) in EOR applications. Several analytical techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM) were applied to confirm the validity of the synthesized NCs. From the synthesized NCs, nanofluids were prepared at different concentrations of 100-2000 ppm and characterized using electrical conductivity, IFT, …

Fabricating 3-Dimensional Human Brown Adipose Microtissues For Transplantation Studies, Ou Wang, Li Han, Haishuang Lin, Mingmei Tian, Shuyang Zhang, Bin Duan, Soonkyu Chung, Chi Zhang, Xiaojun Lian, Yong Wang, Yuguo Lei

Department of Chemical and Biomolecular Engineering: Faculty Publications

Transplanting cell cultured brown adipocytes (BAs) represents a promising approach to prevent and treat obesity (OB) and its associated metabolic disorders, including type 2 diabetes mellitus (T2DM). However, transplanted BAs have a very low survival rate in vivo. The enzymatic dissociation during the harvest of fully differentiated BAs also loses significant cells. There is a critical need for novel methods that can avoid cell death during cell preparation, transplantation, and in vivo. Here, we reported that preparing BAs as injectable microtissues could overcome the problem. We found that 3D culture promoted BA differentiation and UCP-1 expression, and the optimal initial …

Detectability Of Wormholes Through Various Methods, Jonathan W. Keathley

PANDION: The Osprey Journal of Research and Ideas

There are three methods that can possibly detect wormholes: Negative Temperature, Hawking/ Phantom Radiation, and Kα iron emission lines. This paper discusses whether or not any of these three methods are useful ways to detect wormholes with today’s technology and if so, which one is the best and which is the worst. As it turns out, all of these methods have their flaws and impracticalities. After looking through all the evidence and comparing it to what capabilities we have currently, there is clearly a best and worst method. The best method to detect possible wormhole candidates is through the detection …

Tuning The Structural Properties Of Cellulose Acetate Thin Films: A Demonstration Of Confinement And Antiplasticization In Cellulose Acetate Butyrate, Keegan Reece Parkhurst

Graduate Theses - Chemical Engineering

The development of high-performance cellulose acetate thin-film composite membranes will be essential to solving the growing water scarcity problems. To do this, understanding the fundamental structure of thin cellulosic films and its relation to transport is essential. In this work, thin cellulose acetate butyrate films were fabricated at varying thickness and treatments, such as soaking and plasticizer treatment. Their mechanical properties were analyzed using a surface wrinkling approach, and their hygroscopic properties were measured using swelling measurements and surface wrinkling under humid conditions. This work demonstrates confinement in cellulose acetate butyrate films at thicknesses below 45 to 70 nanometers. Plasticization …

Biochar Preparation, Investigation Of Properties And Application As A Low-Cost Adsorbent – A Review, A Kh Aripov, S M. Turabdzhanov, Sh Komilova, O Sh Qodirov, G S. Rakhimova, T V. Darabkova, Zh Aimenova, L S. Rakhimova

Technical science and innovation

An overview of current developments in biochar application in water and wastewater treatment is given in this article, along with a brief explanation of the sorption mechanisms for removing contaminants and the techniques for biochar preparation. In order to encourage the continued use of biochar in effective water and wastewater treatment, future research directions and environmental concerns about biochar are also presented.

Features Designing Special Clothing For The Hot Climate Of Uzbekistan, N Kh Mirtalipova, N A. Isaxujayeva

Technical science and innovation

This paper considers the issues of establishing the relationship between the properties of fabric, clothing design and the comfort of clothing; communication of the size of the human body, allowance for free fitting, modern design when developing the design of clothing; connection of the allowance for free fitting with a suitable air gap. A diagram is given that characterizes the dependence of the comfort of clothing on its design and properties of fabrics. A mathematical model of the processes of air exchange in the underwear space is considered, which will allow obtaining more complete information and establishing more stringent dependences …

Extraction Of Cellulose Nanocrystals From Secondary Paper Waste And Their Use In Paper Production, E A. Egamberdiev, S K. Norboyev

Technical science and innovation

Cellulose nanocrystals were obtained by hydrolysis process from waste paper industry. The result of Fourier transform infrared spectroscopy (FTIR) for nanocellulose showed that no new chemical bonds were formed during the preparation of nanocellulose. The results of X-ray diffraction showed that the crystallinity of the macules produced in the treated and untreated paper industry was 66% and 73.8%, respectively. The results of nanocellulose revealed a natural needle-like fiber with a length of 300 nm to 600 nm, a diameter of 10 nm to 30 nm, and an aspect ratio in the range of 10 to 60. It was found that …

Fluoride Technology For Processing Copper Production Slag At Almalyk Mmc And The Possibility Of Its Application For The Synthesis Of Highly Dispersed Silica Dioxide, M Sh Kurbanov, U M. Nuraliev, J A. Panjiev, S A. Tulaganov, M Ernazarov, L S. Andriyko

Technical science and innovation

A new pilot-plant equipment of an inclined rotary furnace for the processing of fluoroammonium silicon-containing materials has been developed and manufactured, which allowed sublimation of ammonium hexafluorosilicate, formed as a result of fluorination of processed raw materials, in two sections, with autonomous control of temperature and movement of raw materials. It is shown that the use of the created equipment for the processing of copper-smelting slags of the Almalyk MMC using fluoride technology makes it possible to separate amorphous silicon dioxide in the form of a dispersed powder from slags, extract iron and obtain a collective concentrate of precious, non-ferrous …

Selective Reduction Of Trivalent Iron In Zinc Ferrite Using Elemental Sulphur, B T. Berdiyarov, Sh T. Khojiev, J B. Ismailov, S T. Matkarimov, Sh O. Ismatov

Technical science and innovation

In this article, the process laws and technological aspects of the process of sintering the zinc-containing waste of a zinc plant with technical sulfur are considered. Zinc cake is obtained during the sulfuric acid leaching of calcined zinc ores and contains about 20% zinc and additional metals such as indium, cadmium, lead and copper. Copper cakes are somewhat difficult to work with because they contain ferrites and silicates belonging to acid-resistant spinels. Since the chemical and mineralogical composition of zinc production cakes consists of complex oxides, finding ways to process them is one of the actual topics of zinc metallurgy. …