Chemical Engineering Commons^™

Preparations And Electrocatalytic Ethanol Properties Of Palladium Intercalated Hydrotalcite, Shou-Xun Hu, Liang Li, Jun-Hao Yang, Liu-Qiang Li, Zhi-Hao Jin

Journal of Electrochemistry

High-performance electrocatalysts play a vital role in the commercial application of direct fuel cells. Current anode materials still have such problems as low activity, easy poisoning and high cost. In this study, a new type of nano- palladium (Pd) catalyst was prepared by dipping method using layered double hydroxides (LDHs) as the carrier. X-ray diffractometer, scanning electron microscope (SEM), inductively coupled plasma mass spectrometer (ICP-MS), energy spectrometer, transmission electron microscope (TEM), cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscope were used to analyze the structure and electrocatalytic performance of the catalyst. The results showed that the newly prepared Pd/Mg-Al-LDHs still maintained …

Preparation Of Pdcoir Tetrahedron Nanocatalysts And Its Performance Toward Ethanol Oxidation Reaction, Zhi-Yuan Yu, Rui Huang, Jie Liu, Guang Li, Qian-Tong Song, Shi-Gang Sun

Journal of Electrochemistry

As a new energy conversion device, direct ethanol fuel cells (DEFCs) are widely concerned because of their remarkable advantages such as high theoretical energy density and wide fuel sources. However, the rapid development of DEFCs has been severely impeded due to the sluggish kinetic process and toxic intermediates especially in their anodic reactions. Palladium (Pd)-based materials are considered to be excellent anode catalysts for DEFCs, especially under alkaline conditions. And further improving their performance is an important direction to promote the development of DEFCs. Surface structure and composition are the key factors affecting the performance of catalysts which can be …

Research Progress In Electrodeposition Technology Of Titanium-Based Iridium Oxide Electrode, Dan-Dan Wu, Xu Wu

Journal of Electrochemistry

Titanium-based iridium oxide electrode has been widely used in various fields, such as electrocatalytic oxidation, biomedical applications, hydrometallurgical metal recovery, electro-osmotic dewatering, etc. At present, it is mainly prepared by traditional thermal decomposition method, however, which has high cost, cumbersome process, mainly relying on manual labor and cannot be mass-produced yet. It is, therefore, urgently necessary to explore new preparation technologies by focusing on electrodeposition technology, with technological characteristics such as eco-friendly and sustainable development. This article systematically discusses the research progress in iridium oxide electrodeposition preparation technology from the aspects of deposition solution formulation, base material selection and treatment, …

Syntheses Of Na3V2(Po4)2O2F As A Cathode For Sodium Ion Battery Application, Kai Wu

Journal of Electrochemistry

High-temperature solid-state method, hydro-thermal method and solvo-thermal method have been mainly employed to synthesize Na₃V₂(PO₄)₂O₂F (NVPF) cathode materials. However, these methods are energy consuming and complicated, which is not applicable for a large scale industrial production. In this study, a rather low-temperature (70℃) co-precipitation strategy was proposed to synthesize NVPF cathode materials. The as-prepared NVPF cathode materials showed a spherical shape with a diameter of 400 ~ 500 nm, and exhibited a sodium storage of 105.6 mAh·g^-1 and an efficiency of 90.06%. After a simple thermal process, the specific …

Obtaining Of Bacterial Polysaccharides, Kulonov Abdulaziz, Mirzarakhmetova Dilbar, Turaeva Nigora

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work was to develop a technology for obtaining bacterial exopolysaccharides. The problem was solved by using the bacterial strain Halovibrio variabilis UzAS3 as a polysaccharide producer. The optimal parameters of bacterial cultivation have been determined. A technological scheme for obtaining bacterial polysaccharides has been developed, which includes such stages as the cultivation of bacteria, the separation of bacterial biomass from the culture liquid, desalting, precipitation, washing and drying. The obtained results show that bacteria have a high potential for the yield of bacterial exopolysaccharides (7.1-9.5 mg/ml).

Mathematical Modeling Of The 3(Н)-Quinazolin-4-Onе Synthesis Process, Ziyadullayev Mirjalol, Karimov Rikhsibay, Abdurazakov Asqar, Parmonov Asqar

CHEMISTRY AND CHEMICAL ENGINEERING

The aim is to optimize the conditions for the synthesis of 3(H)-quinazolin-4-one by the method of mathematical modeling to develop a technology for producing the substance of a new domestic drug used in the treatment of farm animals from helminths. In mathematical modeling, the method of a small number of squares was used. Analytical dependences of the product yield on temperature, reaction time, and molar ratios of the starting materials were determined. A system of linear equations has been compiled. The system of linear equations was performed by the matrix method (A, B, C).The average reaction rate was determined. Based …

Study Of The Influence Of Construction And Mode Parameters On The Hydrodynamics Of A Hollow Vortex Apparatus, Bakhronov Khoshim, Akhmatov Abdumalik, Juraev Dadakhon

CHEMISTRY AND CHEMICAL ENGINEERING

The research was to determine the more efficient design of the swirler from the point of view of hydrodynamics and heat and its optimal parameters. Various swirl designs were manufactured and tested. After preliminary studies conducted on a laboratory installation with a glass working apparatus, several swirlers were selected taking into account their hydraulic resistance, the structure of the swirling gas-liquid flow, and the amount of liquid entrainment by gas. The results of an experimental study of the hydrodynamics of a hollow vortex apparatus with one and two tangential and axial swirlers. Hydraulic losses in the channel and in the …

Ethinylation Reactions Of Some Aldehydes In The Presence Of Phenylacetylene Using High-Base Catalytic Systems, Abdurakhmanova Saida, Ikramov Abduvaxab, Ziyadullayev Odiljon, Ablakulov Lochin

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research work is the development of synthesis methods of aromatic acetylene alcohols and their various derivatives using different catalytic systems and also, determining their structure, physico-chemical and biological properties. The most effective way of synthesizing AAA is determined using selected complex catalytic systems and also, the range of catalytic activity of used catalysts is created. Acetic aldehyde, benzaldehyde and cyclohexonal, high-base catalytic systems − MOH/ДМСО∙H2O and M2CO3/ДMСO∙H2O with phenylacetylene reaction of enantioselective etynilation were investiged. Efficiency and course of chemical reaction in the process of formation acetylene alcohol affection of temperature, reaction duration, solvents, catalysts and …

Synthesis Of Meta-Altered Arylmaleinamide And Preparation Of Esters In Their Presence, Turaeva Khurshida, Yuldasheva Mukhabbat, Khaydarova Sadokat

CHEMISTRY AND CHEMICAL ENGINEERING

The development of new methods of synthesis using cheaper reagents for the preparation of maleic acid derivatives, the study of chemical properties and the determination of new directions for the practical application of maleic acid derivatives are still relevant. Therefore, the development of this work is an urgent task. The aim of this study was to obtain the synthesis of monomaleinamide compounds under various conditions to obtain arylmaleimide derivatives of maleic acid and to transfer them in a pure state for further reactions. In this study, scientific studies were carried out to find convenient methods for the preparation of monoamide …

Transforming Corn Stover To Useful Transport Fuel Blends In Resource-Limited Settings, Nicholas Munu, Noble Banadda, Nicholas Kiggundu, Ahamada Zziwa, Isa Kabenge, Jeffrey Seay, Robert Kambugu, Joshua Wanyama, Albrecht Schmidt

Chemical and Materials Engineering Faculty Publications

Development of local technologies is crucial to the sustainable energy agenda in resource-limited countries and the world. Strengthening local green technologies and promoting local utilization will reduce carbon emissions that could be generated during transportation and delivery of green products from one country to another. In this paper we developed bio-oil/diesel blends using a low-tech pyrolysis system designed for smallholder farmers in developing countries and tested their appropriateness for diesel engines using standard ASTM methods. Corn stover retrieved from smallholder farmers in Gayaza, Uganda were pyrolyzed in a batch rocket stove reactor at 350 °C and liquid bio-oil harvested. Bio-oil …

Open-Field Scale-Model Experiments Of Fire Whirls Over L-Shaped Line Fires, Yuto Iga, Kazunori Kuwana, Kozo Sekimoto, Yuji Nakamura

Progress in Scale Modeling, an International Journal

This paper presents the results of open-field scale-model experiments of fire-whirl formation over line fires. L-shaped line fires were burned in crosswinds, and the processes of fire-whirl formation were observed. The flame height was measured using an image-processing technique, while two-dimensional velocity components were measured at two different locations using ultrasonic anemometers. Two tests were selected for comparison: test A, in which intense fire whirls repeatedly formed, and test B, in which no whirls were observed. In test A, the wind flow was bent by the fire plume, creating swirling flows near the burning area, thereby forming fire whirls. On …

Coarse-Grained Simulation Of Pegylated And Tethered Protein Devices At All Experimentally Accessible Surface Residues On Β-Lactamase For Stability Analysis And Comparison, Addison K. Smith, Mehran Sultani, Joshua Wilkerson, Brandon Timmerman, Emily Long Zhao, Bradley C. Bundy, Thomas A. Knotts

Faculty Publications

PEGylated and surface-tethered proteins are used in a variety of biotechnological applications, but traditional methods offer little control over the placement of the functionalization sites on the protein. Fortunately, recent experimental methods functionalize the protein at any location on the amino acid sequence, so the question becomes one of selecting the site that will result in the best protein function. This work shows how molecular simulation can be used to screen potential attachment sites for surface tethering or PEGylation. Previous simulation work has shown promise in this regard for a model protein, but these studies are limited to screening only …

An Investigation Of Cross-Links On Crystallization And Degradation In A Novel, Photocross-Linkable Poly (Lactic Acid) System, Nicholas Baksh

USF Tampa Graduate Theses and Dissertations

Polymeric molecular structure consists of repeating units bonded together. Mechanicalproperties can be altered without affecting chemical makeup by altering the number of these units. Small molecules can be introduced and/or polymers can be modified to form bonds between molecular chains. Cross-linking, as this is called, also introduces mechanical variation with minimal effects on chemical composition. Lastly, polymer chains reorient themselves in response to intermolecular forces. This temperature dependent response is known as crystallization. Although chemistry is unaltered, mechanical properties can depend highly on the percent of the sample that is crystallized.

Cross-linking is known to enhance the mechanical properties of …

Dewetting Induced Lipid Bilayer Multicomponent Scaffold For Synthetic Cell Vesicle And Their Stability, Anjana Khanal

Theses and Dissertations

This thesis introduces a microfluidic method to generate monodisperse water-in-oil-in water double emulsions. The microfluidic method is able to produce double emulsions with high degree of controllability and flexibility on size and number of droplets. We demonstrate this by producing double emulsions containing 1-8 inner water droplets and studied their dewetting phenomena to lipid bilayer scaffold. Our study shows that for the dewetting phenomenon to occur the oil must be volatile, polar and should make low contact angle with the involved interfaces. The chloroform shows self-emulsification behavior in presence of surfactant F127. The topological droplets formation with multiple compartments is …

Effects Of Dimensionless Numbers On Decomposition Of Methane Hydrate, Shoma Shimizu, Genichiro Kushida

Progress in Scale Modeling, an International Journal

It is necessary to elucidate the decomposition and combustion of methane hydrate for fire safety during transportation and storage to utilize it for commercial practice. The amount of methane evolved during the decomposition of methane hydrates is affected by the conditions such as the initial temperature, initial density and ambient temperature. In the present study, the internal temperature of methane hydrate and the amount of methane evolved during its decomposition were investigated by a dimensionless numerical analysis using a transient one-dimensional conduction model from a symmetrical methane hydrate ball heated by ambient air. The numerically calculated central temperature and the …

Copper Oxide Nanoparticle Diameter Mediates Serum-Sensitive Toxicity In Beas-2b Cells, Angie S. Morris, Brittany E. Givens, Aaron Silva, Aliasger K. Salem

Chemical and Materials Engineering Faculty Publications

Copper oxide (CuO) nanoparticles (NPs) are abundant in manufacturing processes, but they are an airway irritant. In vitro pulmonary toxicity of CuO NPs has been modeled using cell lines such as human bronchial epithelial cell line BEAS-2B. In 2D in vitro culture, BEAS-2B undergoes squamous differentiation due to the presence of serum. Differentiation is part of the repair process of lung cells in vivo that helps to preserve the epithelial lining of the respiratory tract. Herein, the effects of serum on the hydrodynamic diameter, cellular viability, cellular differentiation, and cellular uptake of 5 and 35 nm CuO NPs are investigated, …

A Study On Fire Hazards Of Oil Tanks In Urban Areas With Scale Model Experiments, Ho Yin Ng, Yu Wan, Wan Ki Chow

Progress in Scale Modeling, an International Journal

Large fuel tanks are located in an urban area of Tsing Yi in Hong Kong, giving potentially high risks to people living nearby if a fire was to occur. Scale modeling experiments were carried out to investigate the potential of fire hazards. Propanol pool fires with five different scales of oil tanks were studied first. Appropriate tank sizes were then put in a 1/2500 architectural scale model on the Tsing Yi Island to study a fuel tank fire. Results show that the heat and smoke from a fire would affect occupants staying in areas near to the fuel tanks. Fire …

Fingering Behavior Of Flame Spread Over Solid Combustibles, Tsuneyoshi Matsuoka, Kentaro Nakashima, Takuma Kajimoto, Akihiro Yoshimasa, Yuji Nakamura

Progress in Scale Modeling, an International Journal

In this study, the fingering pattern formation and the following flamelet spreading over three different kinds of thick combustibles, i.e., Poly methacrylate (PMMA), Poly ethylene (PE) and Poly carbonate (PC) were observed and the effective Lewis number correlation was validated. Experiments were performed with a narrow channel apparatus. In addition to the kinds of solid fuel materials, the channel height and the oxidizer velocity were varied as experimental parameters. An image analysis method was developed to quantify the number, diameter and spread rate of the flamelets. Replacing the fuel thickness into the thermal thickness, the effective Lewis number which is …

Editors’ Choice-Power-Generating Electrochemical Co2 Scrubbing From Air Enabling Practical Aemfc Application, Yiwei Zheng, Garrett Huang, Mrinmay Mandal, John R. Varcoe, Paul A. Kohl, William E. Mustain

Faculty Publications

Anion exchange membrane fuel cells (AEMFCs) have been widely touted as a low-cost alternative to existing proton exchange membrane fuel cells. However, AEMFCs operating on air suffer from a severe performance penalty caused by carbonation from exposure to CO2. Many approaches to removing CO2 from the cathode inlet would consume valuable energy and complicate the systems-level balance-of-plant. Therefore, this work focuses on an electrochemical solution where CO2 removal would still generate power, but not expose an entire AEMFC stack to carbonation conditions. Such a system consists of two AEMFCs in series. The first AEMFC, which acts as an anion exchange …

The Concept Of Constructing Set-Theoretic Models Of Structures Of Intelligent Multi-Axis Mechatronic Robot Modules, Nazarov Khayriddin Nuritdinovich, Matyokubov Nurbek Rrustamovich, Temurbek Omonboyevich Rakhimov, Pulatov Rustambek Alisher Ugli

Bulletin of TUIT: Management and Communication Technologies

The article discusses the features and areas of application of multi-axis electromagnetic mechatronic modules in modules of mechatronic and robotic systems that allow not only to increase productivity and improve the quality of manufactured products, but also by replacing heavy, monotonous and sometimes associated with a risk to human health, manual labor with a machine to release a person for creative constructive work. The generalized structure of a multi-axis mechatronic module is presented; multiple theoretical models of construction principles for the study of electromagnetic mechatronic modules of robots and robotic systems are constructed. In this case, the main attention is …