Engineering Commons^™

Theoretical Investigation Of The Biomass Conversion On Transition Metal Surfaces Based On Density Functional Theory Calculations And Machine Learning, Wenqiang Yang

Theses and Dissertations

During the past decades, heterogenous catalyzed conversion of biomass to hydrocarbons with similar or identical properties to conventional fossil fuels has gained significantly academic and industrial interest. However, the conventional heterogeneous catalysts such as sulfided NiMo/Al₂O₃ and CoMo/Al₂O₃ used have various drawbacks, such as short catalyst lifetime and high sulfur content of product. To overcome the limitations of the conventional sulfided catalysts, new catalysts must be developed, which requires a better understanding of the reaction mechanism of the biomass conversion. Based on density functional theory, in this thesis, we reported a computational calculation study …

Syntheses, Characterisations And Electrochemical Studies Of Nickel(Ii) And Cobalt(Ii)-Ligand Assisted Cooperative Complexes, Subramaniam Jeevithra Dewi

Student Works (2020-2029)

A newly designed tetradentate ligand L1 (L1 = 3,6-bis(pyrazol-1-yl)-pyridazine) which offers multinucleation sites on its moiety structure has been prepared. The reaction of L1 with different molar ratio of nickel and cobalt salts lead to the formation of di- and tetranuclear complexes [NiII 2(L1)2(CH3CN)4](PF6)4 (1), [NiII 4(L1)4(μ-OH)4](ClO4)4 (2) and [CoII/III(L1)4(μ-CH3O)2(μ-O)2](PF6)3(NO3) (3), which served as the attempt to design of catalysts based on cheap and earth-abundant metals for carbon dioxide reduction. The presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the base controls the nuclearity of the complex formation. In the absence of DBU, complex 1 was formed in dinuclear fashion whereas complex 2 …

Simulation And Optimal Control Of Crude Oil Separation Process At Offshore Facilities To Improve Efficiency Of Oil And Condensate Recovery, Yee Kai Chin

Student Works (2020-2029)

Crude oil separation process is the most crucial process in offshore production facilities in ensuring the well fluid is separated efficiently and persistently. Waxy crude or sluggish feed stream is the major disturbance that could cause operational issues and production loss due to process upset. The main objective of this research is to model offshore crude oil separation process and introduce state space control to optimize the control of total liquid and water level within the permissible range as well as to evaluate the effect of disturbances to the controls. This work presents two different modelling methods in developing three-phase …

Physical And Chemical Characteristics Of Supramolecular Complexes Of Glycirrizinic Acid With Phytohormones, Djuraev Tulqin, Esanov Rakhmatillo, Gafurov Makhmudjon, Kushiev Khabibjon

CHEMISTRY AND CHEMICAL ENGINEERING

The process of formation of supramolecular complexes of glycyrrhizinic acid with some phytohormones (indolylacetic acid, indolylbutyric acid, α-naphthyl acetic acid and kinetin) were studied with the aim of creation the plant growth stimulator. The complexes structure was studied using IR and UV spectroscopy methods. The prepared compounds described by some physicochemical parameters. The stability constants and stoichiometric composition of complexes were determined in an aqueous solution at pH of 7,2 using UV spectrometry method. In result, all complexes have composition as 1:1 ratio, except the kinetin complex which has 2:1 ratio. The stability constants were equal: KGA:IAA=1,86±1×104; KGA:IBA=2,51±1×103; KGA:NAA =2,70±1×103 …

Study Of The Process For The Removal Of Dyeing Matters Of The Plant Occimum Basilicum L. Lamiaceae, Usmonjonova Khulkar, Atkhamova Saida, Dodaev Kuchkor

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is dedicated isolation of anthocyanins by ethanol from herbal plant of Occimum basilicum L. Lamiaceae basis. The were studied influencing of temperature, concentration of ethanol to isolation of anthocyanins. There were passed investigations on studying influence level of heating and hydromodule system of rav material-solvent to maximal isolating of anthocyanins. The colors define by fotokolorometrical method at wave length 400-600 nm. There are shown at 540 nm maximal peak of anthocyanins and it is geven as a grapfical diagram. From the obtained depends on content of alcohol in aquatic solution from outlet of colors is …

The Research Of Conditions For The Formation Of Phenol Formaldehyde Resins Modified With Hydroxyl Containg Polyether Polyol, Magrupov Farkhad, Umarov Sherali, Tohirov Murodjon, Radjabova Zukhra

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was to study the conditions of copolycondensation of phenol alcohol with hydroxyl-containing polyether polyol in the presence of maleic anhydride chain extender in order to obtain modified thermoset phenolic-formaldehyde oligomers. Investigation of the dependence of the content of free phenol, formaldehyde and methylol groups on time during the synthesis of the modified phenol-formaldehyde resin with the ratios hydroxyl-containing polyether polyol:phenol alcohol 1:60 mol/mol and 1:100 mol/mol. It was revealed that maleic anhydride, present in the reaction medium as a copolycondensation catalyst, also participates in copolycondensation reactions as a chain extender. Moreover, as the molar fraction …

Vinylation By 3,6-Dimetyloctin-4-Diol-3,6 Acetylene, Yusupova Lola, Abdukarimova Saida, Rajabov Rustambek, Khalimova Oygul

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research work elaboration of technology of obtaine of acetylene diols and their vinyl ethers. Reaction of formation mono di vinyl ethers as a result vinyl 3,6-dimetyloktin-4-diol-3,6 by acetylene, and also influence of solvents, the catalyst and its quantity, duration of reaction, temperatures is investigated. Are defined speed of reaction. Recommended vinyl 3,6-dimetyloktin-4-diol-3,6 acetylene in the presence of highly basic systems at atmospheric pressure.

Synthesis And Research Of New Heterometal Complexes Cо(Ii), Ni(Ii), Cu(Ii) And Mn(Ii) Based On V(V) And 5-(4-Pyridyl)-1,3,4-Oxadiazole-2(3h)-Thione Lubricants, Pirimova Mehribon, Kadirova Shakhnoza, Rakhmonоva Dilnoza, Ziyayev Abduhakim

CHEMISTRY AND CHEMICAL ENGINEERING

The oxadiazole derivatives complex compounds with metals are biologically active substances. The aim of the study was to study the interaction of the chlorides of Co (II), Ni (II), Cu (II) and Mn (II) with 5-(4-pyridyl)-1,3,4-oxadiazole-2(3H)–thione, ammonium vanadate. Competitive coordination of donor centers, electronic and geometric structures of the ligand molecule were studied on the basis of the quantum-chemical software package Gaussian09 LanL2DZ. It was shown that 5-(4-pyridyl)-1,3,4-oxadiazole-2(3H)-thione ligand is partially coordinated through a localized nitrogen or sulfur atoms at formation of the complex. А procedure was developed for the synthesis of new mixed-metal complexes. The composition and structure of …

Poly(Ethylene Oxide) Based Polymer Electrolytes For All-Solid-State Li-S Batteries, Xue Li, Zheng-Liang Gong

Journal of Electrochemistry

In recent years, research on lithium-sulfur (Li-S) batteries has received much attention because the sulfur positive electrode and the lithium metal negative electrode produce a high theoretical specific capacity (lithium metal ~ 3800 mAh·g^-1, sulfur ~ 1675 mAh·g^-1). In addition, sulfur is considered to be the most promising cathode material for secondary lithium batteries, due to its advantages of low price and environmental friendly. However, the practical application of conventional liquid Li-S batteries is still obstructed by several critical issues, such as lithium ploysulfides shuttle effect, long-term stability of lithium metal anode with organic liquid electrolytes, …

Synthesis And Raman Study Of Hollow Core-Shell Ni1.2Co0.8P@N-C As An Anode Material For Sodium-Ion Batteries, Jia-Hui Chen, Xiao-Bin Zhong, Chao He, Xiao-Xiao Wang, Qing-Chi Xu, Jian-Feng Li

Journal of Electrochemistry

With the increasing demand for large-scale energy storage, great progress has been made in discovering new advanced energy storage materials. Sodium-ion batteries (SIBs) have attracted much attention in recent years due to their use of abundant sodium resources and their comparable electrochemical capacity to lithium-ion batteries (LIBs). In this paper, we developed novel hollow core-shell Ni-Co bimetallic phosphide nanocubes with N-doped carbon coatings (Ni_1.2Co_0.8P@N-C) as the anode material for SIBs. The material was synthesized through a low-temperature phosphorization method using resorcinol formaldehyde (RF) resin coating with a Ni-Co Prussian blue analogue (PBA) as a template and …

Preparations Of Nano-MnoX/Ti Electrocatalytic Membrane Electrode For Catalytic Oxidation Of Cyclohexane Using Intermittent Electrodeposition, Xue Zhou, Hong Wang, Zhen Yin, Yu-Jun Zhang, Jian-Xin Li

Journal of Electrochemistry

Cyclohexanone and cyclohexanol (KA oil) obtained from highly selective oxidation of cyclohexane (CHA) show important industrial value and application prospects. In this work, the intermittent electrodeposition was developed to prepare nano-MnO_x catalyst loading porous tubular titanium membrane electrode (MnO_x/Ti), which was employed to constitute an electro-catalytic membrane reactor (ECMR) for the oxidation of cyclohexane to produce cyclohexanol and cyclohexanone. The surface morphology, crystal structure and electrochemical property of the catalysts were characterized by FESEM, XRD and electrochemical workstation, respectively. The results show that the catalyst prepared by the intermittent electrodeposition displayed nano-flower-like γ-MnO₂. Compared with …

Preparation Of Α-Hydroxylated Acetal From 2-Butanone By Indirect Electrooxidation, Hai-Qing Huang, Ye Miao, Xin-Sheng Zhang

Journal of Electrochemistry

Acetoin (3-hydroxy-2-butanone) is an important food spice. As a platform compound, it is widely used in medicine, tobacco, cosmetics, chemical material and other industries. In this paper, α-hydroxylated acetal, an intermediate of acetoin, was prepared from 2-butanone by indirect electrooxidation in the plate and frame electrolytic cell, in which graphite plates were used as both an anode and a cathode, while KOH as an electrolyte and KI as a catalyst. Acetoin could be prepared by hydrolysis in acidic aqueous solution from acetoin intermediate. The effects of current density, electrolyte flow rate between the plates, 2-butanone concentration and electrolysis temperature …

Electrochemical Oxidation Of Metal Chromium In Odium Hydroxide Aqueous Solution, Ping Han, Hai-Tao Feng, Ya-Ping Dong, Sen Tian, Bo Zhang, Wu Li

Journal of Electrochemistry

Ferrochrome electrolysis technology is a novel method for preparing sodium chromate (Na₂CrO₄). Although the method performs well at soft reaction conditions, controllable process, environmentally friendly production process, etc., the electrochemical oxidation process of metal chromium in NaOH aqueous electrolyte is still unclear. At present, there are few research articles about specific electrochemical oxidation of metal chromium in NaOH aqueous electrolyte. It is, therefore, meaningful to carry out the research in electrochemical oxidation mechanism of chromium. The electrochemical oxidation of metal chromium in 0.01 mol·L^-1 ~ 10 mol·L^-1 NaOH aqueous electrolytes at 20 °C was …

Stability Studies For A Membrane Electrode Assembly Type Co2 Electro-Reduction Electrolytic Cell, Qing Mao, Bing-Yu Li, Wei-Yun Jing, Jian Zhao, Song Liu, Yan-Qiang Huang, Zhao-Long Du

Journal of Electrochemistry

Electro-catalytic reduction is an efficient way to achieve resourcable transformation of CO₂, which is one of the important techniques to solve the global environmental problems originated from excessive CO₂ emission. In this study, a membrane electrode assembly(MEA) type CO₂ electro-reduction electrolytic cell was constucted, which enables CO₂ feeding and real-time KHCO₃ aqueous updating on both sides of the cathode gas diffusion electrode (GDE). By means of the electrolytic cell, effects of KHCO₃ concentration and updating inside the liquid electrolytic chamber on CO₂ electro-reduction activity, production distribution and stability were investigated. The experimental …

Brominated Carbon Materials As Positive Electrodes For Nonaqueous Secondary Lithium-Bromine Batteries, Benjamin Beau Peterson

LSU Doctoral Dissertations

Secondary lithium-bromine (Li-Br₂) batteries have theoretical potentials near 4.1 V vs Li/Li⁺ and capacities more than 2 times greater than conventional Li-ion batteries. Herein, secondary, non-aqueous Li-Br₂ half-cell batteries are reported using a Li metal anode, carbon-coated glass fiber separator, non-aqueous Li-based electrolytes with and without the addition of lithium bromine (LiBr) salt, and positive electrodes consisting of either chemically brominated non-graphitic carbon or carbon derived from the carbonization of metal-organic frameworks (MOFs) with LiBr embedded into the micro- and mesopores of the carbon matrix. The separator is effective in mitigating the transport of Br_{2 …}

From Salt In Solution To Solely Ions: Solvation Of Methyl Viologen In Deep Eutectic Solvents And Ionic Liquids, Jeffrey M. Klein, Henry Squire, William Dean, Burcu E. Gurkan

Faculty Scholarship

Solvation and transport properties of methly viologen dichloride (MVCl2) in 1:2, 1:4, and 1:6 molar mixtures of choline chloride (ChCl) and ethylene glycol (EG), including the deep eutectic solvent (DES) ethaline (1:2 mixture), were studied through the application of the hole theory to measured physical properties, cyclic voltammetry, and Raman spectroscopy. The ChCl:EG mixtures were compared to the ionic liquid (IL) 1-methyl-1-propylpyrrolidinium bis(trifluoromethylsulfonyl) imide ([PYR13][TFSI]) and choline bis(trifluoromethylsulfonyl)imide (ChTFSI) EG mixtures with the same molar ratios in order to understand the impact of the anion and hydrogen bond donor on solvation. Exchanging the chloride anion with TFSI is found to …

Biogas Upgrading Via Solid Resin-Based Amine Sorbents, Olusola Johnson

USF Tampa Graduate Theses and Dissertations

Biogas is a valuable renewable energy generated from anaerobic digestion of biodegradable organic matter. It is applicable as fuel in vehicles, for the generation of electricity, industrial heating, or as raw material to produce chemicals, liquid fuels, syngas, and compressed natural gas (CNG). Carbon dioxide (CO2) and methane (CH4) are the major components in biogas, with a trace amount of contaminants, including hydrogen sulfide (H2S), water vapor (H2O), nitrogen (N2), ammonia (NH3), oxygen (O2), carbon monoxide (CO), halides, volatile organic compounds (VOCs), siloxanes, and hydrocarbons.

The source of biogas, which is anaerobic digestion of different organic matter or landfill decomposition, …

Bijels Made By Solvent Transfer Induced Phase Separation: Formation Principles And Transport, Stephen Boakye-Ansah

Theses and Dissertations

Bijels are made of non-equilibrium particle-stabilized emulsions with a bicontinuous arrangement of the constituent fluid phases. They spontaneously form through arrested spinodal decomposition in mixtures of partially miscible liquids and neutrally wetting colloidal particles. Soon after their discovery over 10 years ago, Prof. Mike Cates, Lucasian Professor of Mathematics, predicted their future use as continuously operated cross-flow reactors for chemical reactions between immiscible reactants.

Towards this goal, work in this thesis focuses on designing bijels via Solvent Transfer Induced Phase Separation (STrIPS) for microfluidic transport applications. Structure-function relationships of STrIPS bijels stabilized by silane functionalized nanoparticles are developed. In-situ surfactant …

Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff

Faculty Publications

Biodiesel offers several environmental benefits and improvements to some fuel performance properties, but its poor oxidative stability has been a major concern. Currently, the accepted practice to improve biodiesel oxidative stability is the addition of antioxidants; numerous antioxidants have been studied but their effectiveness in inhibiting biodiesel oxidation is difficult to predict due to variation with resonance stability, solubility, reactivity, and volatility. To improve prediction efforts, this study explored the Rapid Small-Scale Oxidation Test (RSSOT) as a means to investigate how biodiesel oxidation is affected by antioxidant concentration and temperature, and compared its results with the oxidative stability index test. …

Feasibility Of Tempo-Functionalized Imidazolium, Ammonium And Pyridinium Salts As Redox-Active Carriers In Ethaline Deep Eutectic Solvent For Energy Storage, Brian Chen, Nicholas Sinclair, Jesse Wainright, Burcu E. Gurkan

Faculty Scholarship

The discovery of electrolytes that have low vapor pressures and high solubility towards redox active species with an ability to undergo multiple electron transfer reactions is a challenge to realize in large-scale energy storage. Herein, we investigate the feasibility of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) derived halide salts as redox active species in ethaline (1 : 2 ethylene glycol : choline chloride), a deep eutectic solvent (DES). Hydrogen bonding and electrostatic interactions achieved by the functionalization of TEMPO are shown to improve solubility in ethaline. This is the first study evaluating the physical properties and electrochemical behavior of the newly synthesized TEMPO-salts in …

Study Of Recombinant Protein Fractions From The Bombyx Mori And Pichia Pastoris Using "Native Page" Method, Abdurhakhmanov Aloliddin, Sasmakov Sobirdjan, Khasanov Shuhrat, Ashirov Оybek

CHEMISTRY AND CHEMICAL ENGINEERING

We have studied the recombinant protein fractions of ̴ 24-34 kDa obtained from Bombyx mori - silkworm larvae and yeast Pichia pastoris. Fractions, containing the recombinant proteins by gel-electrophoresis using the “Native PAGE” method, which allows for differentiation of proteins according to their natural (surface) charge and conformational properties were studied. The results showed that the recombinant protein fraction from Bombyx mori (̴ 34 kDa) consisted of four components and fraction from Pichia pastoris (̴ 24 kDa) consisted one component. The most optimal conditions for the “Native PAGE”- the main gel: Tris HCl (pH-8.8) 244 mM, Bis-Acrylamide 10%, TEMED 0.08%, …

Pressure-Compensated Temperature Control In Rectification Column, Norkobilov Adham, Turakulov Zafar, Kamolov Azizbek, Talipov Hojiakbar

CHEMISTRY AND CHEMICAL ENGINEERING

The focus of this work is to study the control of a rectification column (RC) for separating n-butane (nC4) and n-pentane (nC5) mixtures. Two control structures based on conventional temperature control (TC) and pressure-compensated control (PTC) structures are studied and compared using Aspentech software. The control performance of TC and PTC are investigated in terms of the control of component purities in both distillate and bottoms streams, under various disturbances in feed and pressure conditions. Due to pressure compensation, PTC is superior to TC in terms of purity and impurity control under disturbances in feed and pressure conditions. Accordingly, simulation …

Research Of Kinetic Characteristics Of The Process Of Decomposition Of Zinc Concentrate With Hydrochloric Acid, Rosilov Mansur, Deng Tianlong, Usmanov Ilham, Samadiy Murodjon

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the study was the theoretical justification of the kinetic characteristics of the process of producing zinc chloride from zinc concentrate of the Khandiza deposit. For this, the effect of temperature and duration of the process of autoclave zinc extraction in a 28% hydrochloric acid solution was studied at a ratio of Zn: HCI = 1:1.1. Variable parameters were the temperature of 70, 80 and 90 °C and the duration of the leaching process of 6, 8 and 10 hours. The optimal parameters for the production of zinc chloride were determined.

The Study Of The Component Composition Of The Reaction Mixture Containing Formaldehyde Reaction Products, Hurramov Lochinbek, Alimukhamedova Nozima, Adilov Ravshan, Alimukhamedov Muzafar

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the effect of the conditions of the reaction of monoethanolamine (Meol) with formaldehyde (FD) on the composition of the reaction mixture. Interaction of monoethanolamine with formaldehyde leads to the formation of N,N’,N”-tris(β-oxyethyl) hexahydro-S-triazine or N,N-bisoxazolidine. The type of final product was determined by the conditions of the reaction and the molar ratio of aminoalcohol:formaldehyde. The chromatogram of the vacuum-distilled final product obtained at the molar ratio of monoethanolamine:formaldehyde=1:1 shows on an individual compound with a retention time of 4.173 s. With increase in the molar ratio of monoethanolamine:formaldehyde=1: 2, the final product …

Study And Characterization Of Conductive Elastomers For Biomedical Applications, Hadis Gharacheh

Theses and Dissertations

Health issues have always been one of humankind's biggest challenges. Over the last century, there has been significant and monumental progress in health and biomedical science, with the end goal of alleviating and eliminating illnesses and ailments. For developing biomedical devices, polymers and elastomers group among other types of biomaterials have been highlighted to be used due to high flexibility, stability, biocompatibility, and mechanical and rheological characteristics. In this work, the characterization of acrylated poly glycerol_sebacate (PGSA) polymer conjugated with bio ionic liquid (BIL) was investigated. Results showed high biocompatibility, high printability with tunable mechanical, adhesive, and conductivity properties. For …

Investigation Of The Process Of Self-Discharge Acid Batteries, Asilbek Kiryigitovich Mamatkulov, Eldor Ikromovich Ruzmatov, Gulniso Yulchievna Zhumaeva, Furkat Ilyasovich Erkabaev

Chemical Technology, Control and Management

In this study, investigations were conducted on the process of self-discharge of acidic car batteries. The dependence of battery discharge on environmental temperature has been studied. It was found that the self-discharge of batteries increases by up to 60% over 12 months when the temperature rises from +10⁰C to +40⁰С. Replacing the tin in the electrode alloy with a more electronegative metal has been shown to reduce the self-discharge process by up to 2% per month. Because, the self-discharge of electrode batteries made of lead-calcium alloy is relatively low, the consumption of working fluid is relatively …

Methods Of Organizing Energy-Closed Technology, Nadirbek Rustambekovich Yusupbekov, Shuxrat Manapovich Gulyamov, Yusuf Shodiyevich Avazov, Nasiba Djumabayevna Xodjiyeva

Chemical Technology, Control and Management

The classification of methods for analyzing energy-technological processes is conducted Promising methods are considered: exergetic, thermo econometric, thermal diagram method, information-thermodynamic method, and method based on the consideration of the irreversible process of heat transfer of an object to the environment. A comparative assessment of the considered methods is given and the expediency of their use is justified.

Mathematical Modeling Of Thermal Processes Of Traction Asynchronous Engines For Diagnosis And Control Of Their Technical Condition, Nilufar Rabbanaqulovna Avezova, Javharbek Sulton Ugli Fayzullayev

Chemical Technology, Control and Management

Mathematical models of thermal processes of traction asynchronous motors are developed. A traction asynchronous motor is considered as a thermal system consisting of three bodies (stator winding, stator magnetic core and rotor), which take into account the heat exchange not only between the corresponding bodies, but also the heat exchange between each body and the environment. It is shown that the steady excess of the stator winding temperature of a traction asynchronous motor depends on the multiplicity of the stator winding current, the coefficient of electrical energy loss, and also on the temperature coefficient of the resistance of the winding …

Remote Measurement Of Plant Biomass By Picosecond Laser Radiation, Abdushukur Abdugafurovich Mukhamedov, Abdirashid Saribaevich Rysbaev, Shamsiddin Norchaevich Ernazarov

Chemical Technology, Control and Management

A description is given of a high-speed optical recording system that uses a solid-state yttrium-aluminum garnet Nd3+ laser that generates a train of picosecond laser pulses. It is shown that by registering and temporarily scanning the secondary fluorescence radiation excited by a sequence of picosecond pulses, it is possible to remotely determine the biomass of plants based on a prematurely created bank of laboratory data.

International Higher Education Cooperation Under Conditions Of Fuzzy Terminology: Intellectual Mobility Vector, Ulugbek Vasikovich Mannanov, Igor Ivanovich Gancherenok

Chemical Technology, Control and Management

Terminology analysis of higher education internationalization process concerning joint educational programs is fulfilled. Fuzziness of used terminology is demonstrated. Joint higher education establishments development in the framework of fractal model is suggested as a strategic direction of higher education internationalization, enhancement of its quality and a concept of effective intellectual mobility.