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2022

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Articles 91 - 120 of 657

Full-Text Articles in Chemical Engineering

Preparation Of N-, O-, And S-Tri-Doped Biochar Through One-Pot Pyrolysis Of Poplar And Urea Formaldehyde And Its Enhanced Removal Of Tetracycline From Wastewater, Wenran Gao, Zixiang Lin, Shanshan Yan, Yaxuan Gao, Hong Zhang, Xun Hu, Hongqi Sun, Shu Zhang Nov 2022

Preparation Of N-, O-, And S-Tri-Doped Biochar Through One-Pot Pyrolysis Of Poplar And Urea Formaldehyde And Its Enhanced Removal Of Tetracycline From Wastewater, Wenran Gao, Zixiang Lin, Shanshan Yan, Yaxuan Gao, Hong Zhang, Xun Hu, Hongqi Sun, Shu Zhang

Research outputs 2022 to 2026

In this study, biochar was prepared via hybrid doping of N, O, and S by applying one-pot pyrolysis of poplar wood and S-containing urea formaldehyde at 900 °C. Different doping ratios were adopted, and the contents of O, N, and S were in the ranges of 2.78 – 5.56 %, 2.16 – 4.92 %, and 1.42 – 4.98 %, respectively. This hybrid doping significantly enhanced the efficiency of the removal of tetracycline (40 mg/L) from wastewater to 71.84 % in comparison with that attained by using normal poplar biochar (29.45 %). The adsorption kinetics and isotherms indicated that the adsorption …


Utilizing Date Pits In Microencapsulation: Effect Of Different Variations On Probiotic Survivability Under In Vitro Digestion, Asmaa Samir Al Hamayda Nov 2022

Utilizing Date Pits In Microencapsulation: Effect Of Different Variations On Probiotic Survivability Under In Vitro Digestion, Asmaa Samir Al Hamayda

Theses

This work deals with the medicinal use of date pit powder, which turns it from a waste product to a useful stabilizer for the release of beneficial probiotics in the human intestine. The main objective of this work is to encapsulate probiotics with date pit beads and their subsequent release in the human intestine. The beads were formed using gravitational dripping technique, while INFOGEST protocol was used to test the digested beads and the release of viable probiotic cells. For the three date varieties Raziz, Naghal and Khadrawy, it was found that 0.1 g of date pit powder per 0.2 …


Biodegradable Heat Insulation Composites Based On Poly(Β-Hydroxybutyrate) And Date Palm Wood, Amal Ibrahim Mlhem Nov 2022

Biodegradable Heat Insulation Composites Based On Poly(Β-Hydroxybutyrate) And Date Palm Wood, Amal Ibrahim Mlhem

Theses

Residential buildings contribute the most to energy consumption. It was found that energy savings of 20% can be achieved through the thermal insulation of residential buildings in the United Arab Emirates. For this reason, research has been conducted in the field of sustainable thermal insulation materials. Wood-Plastic Composites (WPC) are a relatively new generation of biocomposites and are particularly suitable for construction and building applications, which offers high thermal and acoustic insulation properties., reducing carbon emissions and decreasing negative impacts on the environment due to their biodegradability, sustainability, renewability, and recyclability. The first part of this study investigated the thermal …


Phase Transitions And Photoluminescent Properties Of Anion-Engineered Y2o3, Maharram Jabrayilov Oct 2022

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 Oct 2022

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 Oct 2022

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 …


Catalytic Effect Of Disordered Ru-O Configurations For Electrochemical Hydrogen Evolution, Xue Sun, Ya-Jie Song, Ren-Long Li, Jia-Jun Wang Oct 2022

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 Oct 2022

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 …


Alkaline Seawater Electrolysis At Industrial Level:Recent Progress And Perspective, Tao Zhang, Yi-Pu Liu, Qi-Tong Ye, Hong-Jin Fan Oct 2022

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 Oct 2022

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 …


Method For Routine Density Measurement Of Sublimating Solid Carbon Dioxide (Dry Ice) For Cold-Chain Quality Control, Kimberly Hafner, Bruce A. Welt, William Pelletier Oct 2022

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 Oct 2022

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 Oct 2022

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 …


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 Oct 2022

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 …


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 Oct 2022

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, …


Detectability Of Wormholes Through Various Methods, Jonathan W. Keathley Oct 2022

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 Oct 2022

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 Oct 2022

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.


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 Oct 2022

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 Oct 2022

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. …


Features Designing Special Clothing For The Hot Climate Of Uzbekistan, N Kh Mirtalipova, N A. Isaxujayeva Oct 2022

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 Oct 2022

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 …


Élimination Des Vapeurs Toxiques Par Oxydation : Développement De Procédures D'Évaluation Des Systèmes De Purification De L'Air Des Conduits De Ventilation, Chang-Seo Lee, Fariborz Haghighat, Alireza Haghighat Mamaghani, Zahra Shayegan, Ali Bahloul, Mélanie Huard, Lexuan Zhong, Mitra Bahr Oct 2022

Élimination Des Vapeurs Toxiques Par Oxydation : Développement De Procédures D'Évaluation Des Systèmes De Purification De L'Air Des Conduits De Ventilation, Chang-Seo Lee, Fariborz Haghighat, Alireza Haghighat Mamaghani, Zahra Shayegan, Ali Bahloul, Mélanie Huard, Lexuan Zhong, Mitra Bahr

Rapports de recherche scientifique

L'exposition à des composés organiques volatils (COV) dans les lieux de travail peut avoir des effets aigus, notamment sous forme d'irritation de la peau, des yeux, de la bouche et du nez. Certains produits peuvent également provoquer des effets chroniques, comme l'asthme et le cancer. La prévention de tels effets nocifs sur la santé des travailleurs par l'adoption et la mise en œuvre de mesures visant à en éliminer ou à tout le moins réduire le risque s'avère importante. Parmi les approches développées à ce jour pour réduire l'exposition aux polluants de l'air intérieur – dont les COV –, la …


Removal Of Toxic Vapors By Oxidation: Development Of Laboratory Test Procedures For In-Duct Air Cleaning Systems, Chang-Seo Lee, Fariborz Haghighat, Alireza Haghighat Mamaghani, Zahra Shayegan, Ali Bahloul, Mélanie Huard, Lexuan Zhong, Mitra Bahr Oct 2022

Removal Of Toxic Vapors By Oxidation: Development Of Laboratory Test Procedures For In-Duct Air Cleaning Systems, Chang-Seo Lee, Fariborz Haghighat, Alireza Haghighat Mamaghani, Zahra Shayegan, Ali Bahloul, Mélanie Huard, Lexuan Zhong, Mitra Bahr

Rapports de recherche scientifique

L'exposition à des composés organiques volatils (COV) dans les lieux de travail peut avoir des effets aigus, notamment sous forme d'irritation de la peau, des yeux, de la bouche et du nez. Certains produits peuvent également provoquer des effets chroniques, comme l'asthme et le cancer. La prévention de tels effets nocifs sur la santé des travailleurs par l'adoption et la mise en œuvre de mesures visant à en éliminer ou à tout le moins réduire le risque s'avère importante. Parmi les approches développées à ce jour pour réduire l'exposition aux polluants de l'air intérieur – dont les COV –, la …


Prototype Catalytic Membrane Reactor For Dimethyl Ether Synthesis Via Co2hydrogenation, Qiaobei Dong, Weiwei L. Xu, Xiao Fan, Huazheng Li, Naomi Klinghoffer, Travis Pyrzynski, Howard S. Meyer, Xinhua Liang, Miao Yu, Shiguang Li Oct 2022

Prototype Catalytic Membrane Reactor For Dimethyl Ether Synthesis Via Co2hydrogenation, Qiaobei Dong, Weiwei L. Xu, Xiao Fan, Huazheng Li, Naomi Klinghoffer, Travis Pyrzynski, Howard S. Meyer, Xinhua Liang, Miao Yu, Shiguang Li

Chemical and Biochemical Engineering Faculty Research & Creative Works

Dimethyl ether (DME) has become attractive as a potential environmentally friendly substitute for diesel and liquefied petroleum gas (LPG) due to its similar properties to those of LPG, high cetane number, but less carbon emissions. In this work, we developed a novel prototype-scale catalytic membrane reactor to synthesize DME directly from CO2and renewable H2, which could address the environmental and fuel security issues in a cost-effective way. This membrane reactor was equipped with superior hydrophilic NaA zeolite membranes and bifunctional Cu-ZnO-ZrO2-Al2O3/HZSM-5 catalysts. The effects of the reaction temperature and gas …


Serpentine Micromixers Using Extensional Mixing Elements, George Tomaras, Chandrasekhar R. Kothapalli, Petru S. Fodor Oct 2022

Serpentine Micromixers Using Extensional Mixing Elements, George Tomaras, Chandrasekhar R. Kothapalli, Petru S. Fodor

Physics Faculty Publications

Computational fluid dynamics modeling was used to characterize the effect of the integration of constrictions defined by the vertices of hyperbolas on the flow structure in microfluidic serpentine channels. In the new topology, the Dean flows characteristic of the pressure-driven fluid motion along curved channels are combined with elongational flows and asymmetric longitudinal eddies that develop in the constriction region. The resulting complex flow structure is characterized by folding and stretching of the fluid volumes, which can promote enhanced mixing. Optimization of the geometrical parameters defining the constriction region allows for the development of an efficient micromixer topology that shows …


Understanding Unsteady Corner Separation Within Wing-Body Junction Flows, Paul G. Winner Oct 2022

Understanding Unsteady Corner Separation Within Wing-Body Junction Flows, Paul G. Winner

Doctoral Dissertations and Master's Theses

Wing-body junction flows, formed at the interface between a wing and fuselage surface, are a complex, coupled, three-dimensional, turbulent flow field. This thesis focused on the unsteady corner separation that develops at the trailing edge of this wing-body junction under certain conditions. A NACA 0015 wing mounted on a flat plate at an angle of attack of 13°was used as the model junction flow field. The wing had an aspect ratio of 8 with a linear washout twist of 15°. The Reynolds number based on the wing chord was Rec = 4.5 × 105. Time-dependent stereoscopic particle …


Mantle Dynamics Of The North China Craton: New Insights From Mantle Transition Zone Imaging Constrained By P-To-S Receiver Functions, Lin Liu, Stephen S. Gao, Kelly H. Liu, William L. Griffin, Sanzhong Li, Siyou Tong, Jieyuan Ning Oct 2022

Mantle Dynamics Of The North China Craton: New Insights From Mantle Transition Zone Imaging Constrained By P-To-S Receiver Functions, Lin Liu, Stephen S. Gao, Kelly H. Liu, William L. Griffin, Sanzhong Li, Siyou Tong, Jieyuan Ning

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Cratons are generally defined as stable continental blocks with a strong cratonic root that typically is at least ∼200 km thick. Many cratons have undergone little internal tectonism and destruction since their formation, but some of them, such as the eastern part of the North China Craton (NCC), the Dharwar Craton and the Wyoming Craton, have lost their thick cratonic root and become reactivated in recent geological history, leading to widespread Meso-Cenozoic volcanisms. The mechanisms responsible for such decratonization remain debated. To provide new constraints on models leading to decratonization, in this study we stack 612 854 source-normalized P-to-S conversions …


Liquid Phase Modeling In Metal Catalysis And In Zeolites, Subrata Kumar Kundu Oct 2022

Liquid Phase Modeling In Metal Catalysis And In Zeolites, Subrata Kumar Kundu

Theses and Dissertations

Liquid phase processing is often desired for selective product formation, such as during catalytic conversion of biomass, and for purification of waste-water streams. Since the liquid phase environment influences the adsorption properties and reactivity of solid catalysts and porous materials, significant performance changes have been observed as a function of solvent properties for various industrial catalytic and separation processes. There is a need to better understand these solvation effects on processes at solid-liquid interfaces and to develop novel multiscale models that permit one to explore solvation effects on surface catalyzed reactions and during adsorption in porous media such as zeolites. …


Durability Enhancement Of Anion Exchange Membrane Based Fuel Cells (Aemfcs) And Water Electrolyzers (Aemels) By Understanding Degradation Mechanisms, Noor Ui Hassan Oct 2022

Durability Enhancement Of Anion Exchange Membrane Based Fuel Cells (Aemfcs) And Water Electrolyzers (Aemels) By Understanding Degradation Mechanisms, Noor Ui Hassan

Theses and Dissertations

The past several years have seen remarkable progress in renewable energy sources such as solar and wind, showing excellent efficiency and significant cost reduction. The intermittent nature of renewable resources requires them to be integrated with energy storage systems that can hold or convert this excess energy into other forms. Though batteries have been the most popular, it is also possible to store the energy as chemicals and fuels, such as hydrogen (H2). Hydrogen generation from water electrolysis has been receiving significant attention in recent years. Among the existing water electrolysis technologies, anion exchange membrane electrolyzers (AEMELs) are …