Open Access. Powered by Scholars. Published by Universities.®

Chemical Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

14,163 Full-Text Articles 24,786 Authors 7,946,487 Downloads 167 Institutions

All Articles in Chemical Engineering

Faceted Search

14,163 full-text articles. Page 170 of 499.

Investigating Influence Of Geometry And Operating Conditions On Local Current, Concentration, And Crossover In Alkaline Water Electrolysis Using Computational Fluid Dynamics, J. S. Lopata, S-G. Kang, H-S. Cho, C-H. Kim, J. W. Weidner, Sirivatch Shimpalee 2021 University of South Carolina

Investigating Influence Of Geometry And Operating Conditions On Local Current, Concentration, And Crossover In Alkaline Water Electrolysis Using Computational Fluid Dynamics, J. S. Lopata, S-G. Kang, H-S. Cho, C-H. Kim, J. W. Weidner, Sirivatch Shimpalee

Faculty Publications

We use a three-dimensional computational fluid dynamics model to examine the liquid saturation, KOH concentration, and gas crossover in an alkaline diaphragm water electrolysis device. The effects of cell potential, solution feed rate, and aspects of the design such as the locations and widths of channels on performance and crossover were studied. The results build a case for implementing a separator transport model and an electrode/separator interface model because of the concentration changes observed at the anode and cathode. Simulations suggest a strong relationship between solution feed rate and the nature of dissolved gas crossover through the diaphragm due to …


A High Solids Field-To-Fuel Research Pipeline To Identify Interactions Between Feedstocks And Biofuel Production, Meenaa Chandrasekar, Leela Joshi, Karleigh M. Krieg, Sarvada Chipkar, Emily Burke, Derek J. Debrauske, Kurt D. Thelen, Trey K. Sato, Rebecca Ong 2021 Michigan Technological University

A High Solids Field-To-Fuel Research Pipeline To Identify Interactions Between Feedstocks And Biofuel Production, Meenaa Chandrasekar, Leela Joshi, Karleigh M. Krieg, Sarvada Chipkar, Emily Burke, Derek J. Debrauske, Kurt D. Thelen, Trey K. Sato, Rebecca Ong

Michigan Tech Publications, Part 1

Background: Environmental factors, such as weather extremes, have the potential to cause adverse effects on plant biomass quality and quantity. Beyond adversely affecting feedstock yield and composition, which have been extensively studied, environmental factors can have detrimental effects on saccharification and fermentation processes in biofuel production. Only a few studies have evaluated the effect of these factors on biomass deconstruction into biofuel and resulting fuel yields. This field-to-fuel evaluation of various feedstocks requires rigorous coordination of pretreatment, enzymatic hydrolysis, and fermentation experiments. A large number of biomass samples, often in limited quantity, are needed to thoroughly understand the effect of …


Emergence Of Non-Hexagonal Crystal Packing Of Deswollen And Deformed Ultra-Soft Microgels Under Osmotic Pressure Control, Molla R. Islam, Rachel Nguyen, L. Andrew Lyon 2021 Chapman University

Emergence Of Non-Hexagonal Crystal Packing Of Deswollen And Deformed Ultra-Soft Microgels Under Osmotic Pressure Control, Molla R. Islam, Rachel Nguyen, L. Andrew Lyon

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Highly solvent swollen poly(N-isopropylacrylamide-co-acrylic acid) microgels are synthesized without exogenous crosslinker, making them extremely soft and deformable. These ultralow crosslinked microgels (ULC) are incubated under controlled osmotic pressure to provide a slow (and presumably thermodynamically controlled) approach to higher packing densities. It is found that ULC microgels show stable colloidal packing over a very wide range of osmotic pressures and thus packing densities. Surprising observation of co-existence between hexagonal and square lattices is also made over the lower range of studied osmotic pressures, with microgels apparently changing shape from spheres to cubes in defects or grain boundaries. It is proposed …


Dynamic Simulation Of A Novel Nuclear Hybrid Energy System With Large-Scale Hydrogen Storage In An Underground Salt Cavern, An Ho, Kasra Mohammadi, Matthew Memmott, John Hedengren, Kody Powell 2021 University of Utah

Dynamic Simulation Of A Novel Nuclear Hybrid Energy System With Large-Scale Hydrogen Storage In An Underground Salt Cavern, An Ho, Kasra Mohammadi, Matthew Memmott, John Hedengren, Kody Powell

Faculty Publications

In this study, a nuclear hybrid energy system (NHES) with large-scale hydrogen storage integrated with a gas turbine cycle is proposed as a flexible system for load following. The proposed system consists of a nuclear reactor, a steam Rankine cycle, a hydrogen electrolyzer, a storage system for hydrogen in an underground salt cavern, and a Brayton cycle that uses hydrogen as fuel to generate additional electricity to meet peak demand. A dynamic mathematical model is developed for each subsystem of the NHES. To evaluate the potential benefits of the system, a one-year study is conducted, using scaled grid demand data …


Optoacoustically Induced Auditory Brainstem Responses In The Mouse Model Enhanced Through An Absorbing Film, Gabriela Lana 2021 Missouri University of Science and Technology

Optoacoustically Induced Auditory Brainstem Responses In The Mouse Model Enhanced Through An Absorbing Film, Gabriela Lana

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.


Electroanalytical Measurements Of Oxide Ions In Molten Cacl2 On W Electrode, Devin Rappleye, Chao Zhang, Art Nelson, Scott Simpson, Michael Simpson 2021 Brigham Young University - Provo

Electroanalytical Measurements Of Oxide Ions In Molten Cacl2 On W Electrode, Devin Rappleye, Chao Zhang, Art Nelson, Scott Simpson, Michael Simpson

Faculty Publications

The electrochemical interaction of oxide ions with tungsten electrodes in molten calcium chloride (CaCl2) was analyzed by combining electroanalytical techniques with X-ray photoelectron spectroscopy. During a cyclic voltammetry (CV) scan, the oxide ions appear to interact with the tungsten working electrode via a multi-step oxidation and reduction process. The overall redox peaks behave reversibly up to 750 mV/s. This electrochemical process enables the oxide ion concentration to be correlated to CV oxidation peaks. The resulting correlation agrees well (8.8% difference) with back titration measurements and can be used to monitor oxide content in the salt in real-time during …


Comparative Evaluation Of Two Glass Polyalkenoate Cements: An In Vivo Pilot Study Using A Sheep Model, Leyla Hasandoost, Daniella Marx, Paul Zalzal, Oleg Safir, Mark Hurtig, Cina Mehrvar, Stephen D. Waldman, Marcello Papini, Mark R. Towler 2021 Missouri University of Science and Technology

Comparative Evaluation Of Two Glass Polyalkenoate Cements: An In Vivo Pilot Study Using A Sheep Model, Leyla Hasandoost, Daniella Marx, Paul Zalzal, Oleg Safir, Mark Hurtig, Cina Mehrvar, Stephen D. Waldman, Marcello Papini, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Poly(methyl methacrylate) (PMMA) is used to manage bone loss in revision total knee arthroplasty (rTKA). However, the application of PMMA has been associated with complications such as volumetric shrinkage, necrosis, wear debris, and loosening. Glass polyalkenoate cements (GPCs) have potential bone cementation applications. Unlike PMMA, GPC does not undergo volumetric shrinkage, adheres chemically to bone, and does not undergo an exothermic setting reaction. In this study, two different compositions of GPCs (GPCA and GPCB), based on the patented glass system SiO2-CaO-SrO-P2O5-Ta2O5, were investigated. Working and setting times, pH, ion release, …


Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles 2021 CUNY Graduate Center

Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles

Dissertations, Theses, and Capstone Projects

Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these …


Advances In Modeling Gas Adsorption In Porous Materials For The Characterization Applications, Max A. Maximov 2021 New Jersey Institute of Technology

Advances In Modeling Gas Adsorption In Porous Materials For The Characterization Applications, Max A. Maximov

Dissertations

The dissertation studies methods for mesoporous materials characterization using adsorption at various levels of scale and complexity. It starts with the topic introduction, necessary notations and definitions, recognized standards, and a literature review.

Synthesis of novel materials requires tailoring of the characterization methods and their thorough testing. The second chapter presents a nitrogen adsorption characterization study for silica colloidal crystals (synthetic opals). These materials have cage-like pores in the range of tens of nanometers. The adsorption model can be described within a macroscopic approach, based on the Derjaguin-Broekhoff-de Boer (DBdB) theory of capillary condensation. A kernel of theoretical isotherms is …


Shale Softening Based On Pore Network And Laboratory Investigations, Di Zhang 2021 New Jersey Institute of Technology

Shale Softening Based On Pore Network And Laboratory Investigations, Di Zhang

Dissertations

This dissertation consists of two major parts: Firstly, experimental investigation of four major shale softening mechanisms and quantifications of structural parameters. Secondly, numerical simulations of nano-scale flow behaviors using the previous experiments determined parameters based on modified pore network modeling.

Hydraulic fracturing is widely applied to economical gas production from shale reservoirs. Still, the gradual swelling of the clay micro/nano-pores due to retained fluid from hydraulic fracturing causes a gradual reduction of gas production. Four different gas-bearing shale samples are investigated to quantify the expected shale swelling due to hydraulic fracturing. These shale samples are subject to heated deionized (DI) …


Feedstock Powders For Reactive Structural Materials, Daniel Hastings 2021 New Jersey Institute of Technology

Feedstock Powders For Reactive Structural Materials, Daniel Hastings

Dissertations

Metals as fuels have higher energy density per unit mass or volume compared to any hydrocarbon. At the same time, metals are common structural materials. Exploring metals as reactive structural materials may combine their high energy density with attractive mechanical properties. Preparing such materials, however, is challenging. Requirements that need to be met for applications include density, strength, and stability enabling the component to sustain the structure during its desired operation; added requirements are the amount and rate of the energy release upon impact or shock. Powder technology and additive manufacturing are approaches considered for design of reactive structural materials. …


Towards Quality By Design (Qbd) Of Pharmaceutical Oral Films Loaded With Poorly Watersoluble Drugs, Eylul Cetindag 2021 New Jersey Institute of Technology

Towards Quality By Design (Qbd) Of Pharmaceutical Oral Films Loaded With Poorly Watersoluble Drugs, Eylul Cetindag

Dissertations

Oral films are an emerging drug delivery dosage form with numerous advantages such as ease of handling, the possibility to circumvent the first-pass metabolism, better patient compliance, capability for continuous manufacturing, and as a platform for personalized medicine. As films are different from other final dosages by their dimensions and their matrix form, further research is required to better understand the impact of excipient and drug on product performance to assure a consistent and good quality product. Therefore, this dissertation aims to contribute towards the processability and manufacturability of films by examining the impact of the materials and processes. First, …


Exploring Fused Deposition Modeling (Fdm) Three-Dimensional Printing Tablet Design Options For Pharmaceutical Dosage Forms, Guluzar Gorkem Buyukgoz 2021 New Jersey Institute of Technology

Exploring Fused Deposition Modeling (Fdm) Three-Dimensional Printing Tablet Design Options For Pharmaceutical Dosage Forms, Guluzar Gorkem Buyukgoz

Dissertations

This dissertation examines the use of Fused Deposition Modeling (FDM) based three-dimensional (3D) printing approach for developing patient-specific dosage forms and addressing related technical challenges in such drug delivery systems. The first main objective is to explore pharmaceutical tablet design options using novel FDM 3D printing technology as the drug delivery platform such that drug form and tablet properties are tailored by considering patient age-specific formulations and dissolution control. Of the five different design options, two proposed options meet the main objective of providing similar drug release, whereas the popular option of fixed drug concentration but differing tablet size could …


Problems Of Modeling And Control Of The Technological Process Of Ore Grinding, Djalolitdin Pakhritdinovich Mukhitdinov, Sanjar Boybutayev 2021 Tashkent State Technical University, Address: 2 Universitetskaya st., 100095, Tashkent city, Republic of Uzbekistan, E-mail: [email protected];

Problems Of Modeling And Control Of The Technological Process Of Ore Grinding, Djalolitdin Pakhritdinovich Mukhitdinov, Sanjar Boybutayev

Chemical Technology, Control and Management

The article analyzes the methods of mathematical modeling of the closed-loop process of fine grinding of ore in order to predict the composition of the crushed raw material. Analyzed modeling methods that consider the control of classification of crushed raw materials and finished products by the size of the recirculating load, simulation modeling methods, methods that use neuro-phase netthe research apparatus, in which the fuzzy logic apparatus serves as a fundamental component for the formation of conclusions. The materials presented in the article reflect the theoretical substantiation and generalization of the accumulated practical experience in modeling and control of the …


Structural-Parametric Analysis And Synthesis Of Control Systems With Two Degrees Of Freedom, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev 2021 Tashkent State Technical University, Address: 2 Universitetskaya st., 100095, Tashkent city, Republic of Uzbekistan, E-mail: [email protected], Phone: +998-91-135-18-02;

Structural-Parametric Analysis And Synthesis Of Control Systems With Two Degrees Of Freedom, Azizbek Nodirbekovich Yusupbekov, Khurshid Salim Ugli Turayev

Chemical Technology, Control and Management

Automatic tuning of the parameters of PID - regulators is proposed by means of a modified experiment that takes into account the influence of elements and circuits in the form of additive uncertainty. The use of a multiply connected control scheme with two degrees of freedom for decoupling is proposed in order to facilitate the implementation of a mechanism for combating the phenomenon of integral saturation. Equations are derived for the transition from a circuit with one degree of freedom to a circuit with two degrees of freedom for the general and special cases of a two-dimensional system, which makes …


Algorithm For The Synthesis Of The Control System Of A Double Mass Elastic Dynamic Object, Isomiddin Khakimovich Siddikov, Gulchekhra Rakhimjonovna Alimova, Davronbek Abdalimovich Khalmatov 2021 Professor, Department of Information Processing Systems and Control, Tashkent State Technical University, Address: 2 Universitetskaya st., 100095, Tashkent city, Republic of Uzbekistan E-mail: [email protected]: Phone: (88) 700-52-68;

Algorithm For The Synthesis Of The Control System Of A Double Mass Elastic Dynamic Object, Isomiddin Khakimovich Siddikov, Gulchekhra Rakhimjonovna Alimova, Davronbek Abdalimovich Khalmatov

Chemical Technology, Control and Management

There are dealt with the creation of a control system for a dynamic object with an elastic property, described by a system of second-order differential equations, further transformed into two polynomial equations in matrix form in a paper. In order to solve the problem of synthesizing the control system, two matrix polynomials with unknown parameters were introduced into the system of equations, which is the transfer function of the controller, the order of which is two, giving the system the properties of astatism. To solve the delivered problem posed, the matrix polynomial equation was transformed into a matrix linear equation …


Preparation Of Meta-Nitrobenzoylhydrazone Ferrocenoylacetone And Synthesis On Its Basis, Zilola Abduraxmonovna Sulaymonova, Bako Bafayevich Umarov doctor chemical science, professor 2021 Bukhara state university, Adress: 11. st. M. Ikbala, Bukhara city, 200117, Republic of Uzbekistan, E-mail: [email protected]

Preparation Of Meta-Nitrobenzoylhydrazone Ferrocenoylacetone And Synthesis On Its Basis, Zilola Abduraxmonovna Sulaymonova, Bako Bafayevich Umarov Doctor Chemical Science, Professor

Chemical Technology, Control and Management

β-diketone-ferrocenoylacetone was obtained by Claisen condensation. Meta-nitrobenzoylhydrazone of ferrocenoylacetone (H2L) was synthesized by the interaction of meta-nitrobenzoic acid hydrazide with ferrocenoylacetone. On its basis, complexes with copper(II) and nickel(II) ions were synthesized. The obtained compounds were characterized by the methods of elemental analysis, IR-, 1H NMR andelectronic spectroscopy. The research results showed that H2L in solution exists in the form of a tautomeric mixture: hydrazone, α-hydroxyazine, and cyclic 5-hydroxypyrazoline forms. According to the results of IR and 1H NMR spectra, the complexes were assigned a planar-square structure, and in them the doubly deprotonated …


Application Of Methods Of Intermittent Ventilation Of Industrial Premises Using A Digital Data Transmission System, Yuriy Shipulin, Abdullayev Temur, Jamolidin Usmanov, Shahnoza Ergasheva 2021 Tashkent State Technical University after I.Karimov, Address: 2 Universitetskaya st., 100095, Tashkent city, Republic of Uzbekistan, E-mail: [email protected];

Application Of Methods Of Intermittent Ventilation Of Industrial Premises Using A Digital Data Transmission System, Yuriy Shipulin, Abdullayev Temur, Jamolidin Usmanov, Shahnoza Ergasheva

Chemical Technology, Control and Management

The article is devoted to topical applied issues, the application of methods of intermittent ventilation of industrial buildings using a digital data transmission system. The requirements for the parameters of the environment are determined, which include: composition, purity, temperature, air humidity, the content of positive and negative ions, the presence of fields of various origins (thermal, optical, biological, gas, and electromagnetic). The authors of the article argue that some of the listed parameters can be supported by ventilation and air conditioning (SCA) systems.

It is shown that when the controlled parameters are limited to a multidimensional area, the SCA control …


Algorithms For Controlling The State Of Executive Mechanisms, Farkhod Kasimov, Mirkhalil Ismailov 2021 Tashkent State Technical University, Address: 2 Universitetskaya st., 100095, Tashkent, Uzbekistan, E-mail: [email protected], Phone: +998-94-608-19-19;

Algorithms For Controlling The State Of Executive Mechanisms, Farkhod Kasimov, Mirkhalil Ismailov

Chemical Technology, Control and Management

When constructing automatic control systems, the main attention often is paid to determining the optimal parameters of system regulators than other elements that make up the system. The executive mechanisms also significantly affect the function quality of the control system. In this article, the actuators were considered as a sub-system within the control system and control algorithms with open and closed-loop communication relative to the actuators were investigated. To assess the real state of the actuators, and improved control structure with sensors installed on the moving parts has been developed. For this structure, an algorithm for evaluating and controlling the …


Artificial Neural Networks For Measuring The Moisture Of Bulk Materials, Erkin Uljaev, Shohrux Nurali o‘g‘li Narzullayev 2021 Doctor of technical sciences, Professor, Information processing and management systems department at Tashkent State Technical University named after Islam Karimov, Tashkent, Uzbekistan

Artificial Neural Networks For Measuring The Moisture Of Bulk Materials, Erkin Uljaev, Shohrux Nurali O‘G‘Li Narzullayev

Chemical Technology, Control and Management

One of the urgent tasks of industrial production is improving the quality of verification of received, manufactured, and stored products, reducing energy consumption in the production of a final product. The solution to this problem is impossible without the creation of devices that control the quality indicators of materials within the limits of the permissible error. One of the most common indicators of the quality of bulk materials is moisture. In the national economy and industrial production, it is required to determine the moisture content of more than 500 different substances and materials. The paper shows the possibility of using …


Digital Commons powered by bepress