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2019

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Articles 481 - 510 of 10505

Full-Text Articles in Engineering

Lupd - Leisure Underwater Propulsion Device, James Abraham, Tanner Nordell, Holden Schmidt, Noah Trimark Dec 2019

Lupd - Leisure Underwater Propulsion Device, James Abraham, Tanner Nordell, Holden Schmidt, Noah Trimark

Mechanical Engineering Design Project Class

The main objective of this Design Project was to create a hands-free, wearable underwater propulsion device. The target consumer is leisure divers, so managing cost was important. Current products on the market do not allow divers to be hands-free while diving and are very expensive. The design process began with an interview with Josh An, a Masters Degree candidate at Washington University in St. Louis. Josh is an avid diver and wanted to see if it was possible to develop a cheap underwater jet pack for leisure diving. After multiple design concepts and mock up prototypes, our team decided on …


Effect Of Incorporating Pottery And Bottom Ash As Partial Replacement Of Cement, Bassam A. Tayeh, Doha M. Alsaffar, Lawend K. Askar, Asmahan Issa Jubeh Dec 2019

Effect Of Incorporating Pottery And Bottom Ash As Partial Replacement Of Cement, Bassam A. Tayeh, Doha M. Alsaffar, Lawend K. Askar, Asmahan Issa Jubeh

Karbala International Journal of Modern Science

This study addressed the environmental constraints in cement produc­tion. Ordinary Portland cement (OPC) was replaced with pottery powder (PP, produced by grinding locally available pottery) and bottom ash (BA) at 10%, 20% and 30% of cement mass. Moreover, 4% calcium chloride solution (CaCl2.2H2O) was used as mixing water. Material properties, such as standard consistency, setting time and compressive strength, were measured with different percentages of OPC replacement with PP and BA. Results indicated that the replacement with PP and BA increased the water demand to achieve the standard consistency. These results revealed that the strength evolution …


Artificial Bee Colony Algorithm For Solving Fuzzy Multi-Objective Bed Allocation Model, Abdulhakeem Luqman Hasan Dec 2019

Artificial Bee Colony Algorithm For Solving Fuzzy Multi-Objective Bed Allocation Model, Abdulhakeem Luqman Hasan

Karbala International Journal of Modern Science

With the improvement of the medical services frameworks rivalry, hospitals face more and more challenges. In the interim, allotment of resource has a crucial influence on performing competitive benefits in a hospitals. To choose the suitable beds number is one of the most essential tasks in hospital administration. Anyway, in true condition, bed allotment choice is a multiple-side problem with weakness and haphazardness of the information available. It is so sophisticated. Therefore, the research about bed allotment difficulty is comparatively rare under considering multiple departments, nursing hours, and stochastic information about arrival and service of patients. In this paper, we …


Stereo Photogrammetry Vs Computed Tomography For 3d Medical Measurements, Doaa Awda Hussien, Fanar M. Abed, Alauldeen A. Hasan Dec 2019

Stereo Photogrammetry Vs Computed Tomography For 3d Medical Measurements, Doaa Awda Hussien, Fanar M. Abed, Alauldeen A. Hasan

Karbala International Journal of Modern Science

The acquisition of 3D body measurements by computer vision-based remote sensing is becoming extremely substantial in clinical studies nowadays. Thus, accurate 3D models of human anatomical surfaces are required in many clinical routines like disease diagnosis, patient follow-up, surgical planning, computer assisted surgery and different biomechanical applications. These models can be generated from different imaging techniques such as computed tomography (CT). However, 3D conventional medical imaging like CT scan have serious limitations in application such as exposing the patient to ionizing radiation due to repeated scans, highly cost imaging process, failure to provide color texture information, and also lacking to …


Machine Learning On Acoustic Signals Applied To High-Speed Bridge Deck Defect Detection, Yao Chou Dec 2019

Machine Learning On Acoustic Signals Applied To High-Speed Bridge Deck Defect Detection, Yao Chou

Theses and Dissertations

Machine learning techniques are being applied to many data-intensive problems because they can accurately provide classification of complex data using appropriate training. Often, the performance of machine learning can exceed the performance of traditional techniques because machine learning can take advantage of higher dimensionality than traditional algorithms. In this work, acoustic data sets taken using a rapid scanning technique on concrete bridge decks provided an opportunity to both apply machine learning algorithms to improve detection performance and also to investigate the ways that training of neural networks can be aided by data augmentation approaches. Early detection and repair can enhance …


Ice Cream Dispensing Machine, Katie Bahnck, Rachel Lockwood, Marie White, Simone Raeth Dec 2019

Ice Cream Dispensing Machine, Katie Bahnck, Rachel Lockwood, Marie White, Simone Raeth

Mechanical Engineering Design Project Class

Each August, Washington University in St. Louis (WashU) welcomes hundreds of new engineering students to its McKelvey School of Engineering. Historically, during orientation activities, WashU’s Engineering Student Services (ESS) serves dessert bars to the new students, where they must line up and make their own desserts manually. To make the dessert bar more interactive and give students a primer for what their engineering studies hold, we would like to introduce an ice cream sundae making machine to the spread. A semi-automated ice cream machine would allow students to customize their ice cream sundae while observing the everyday mechanics required to …


Jet Beluga: Diver Propulsion Wearable, Jacob Graham, Bernardo Amaral Neves, Ethan Genter Dec 2019

Jet Beluga: Diver Propulsion Wearable, Jacob Graham, Bernardo Amaral Neves, Ethan Genter

Mechanical Engineering Design Project Class

Scuba diving is a physically and mentally challenging task performed in both recreational and professional settings. Recreational divers seek to experience the marine world for extended periods of time without buoyant resistance. Rescue divers, military personnel, and underwater construction workers train to execute complicated tasks in a limited time period. Diver propulsion vehicles can improve the quality of recreational diving as well as the effectiveness of diving as performed in professional settings. The following report describes the design and motivations for a wearable diver propulsion device that provides the benefits of increased speed and mobility while limiting the amount of …


Sweet Spot Demonstration, Andrew Amend, Mitchell Smith, Ian Fish, Curtis Hoffman Dec 2019

Sweet Spot Demonstration, Andrew Amend, Mitchell Smith, Ian Fish, Curtis Hoffman

Mechanical Engineering Design Project Class

Our goal was to design and build an exhibit for the St. Louis Science Center to serve as a teaching tool to help explain the unintuitive concept of a baseball bat’s sweet spot to a typical children museum’s visitor, a 5th grade student, in an interesting and visually pleasing way. The sweet spot of the bat is colloquially known as the place that makes the best contact with the ball, and it is determined by a combination of the center of percussion and location of vibrational nodes. We focused on showing how the location of bat-ball impact affects the vibration …


Sweet Spot Demonstration, Keval Amin, Beau Allen, Kieran Lenssen, Ricardo Del Olmo Parrado Dec 2019

Sweet Spot Demonstration, Keval Amin, Beau Allen, Kieran Lenssen, Ricardo Del Olmo Parrado

Mechanical Engineering Design Project Class

The purpose of this project was to create a sweet spot exhibit for the St. Louis Science Center to demonstrate the basic dynamic and vibrational theory behind the game of baseball. This demonstration focuses on the dynamics of batting and the effects that induced bat vibrations have on the energy transfer from the bat to the ball. Through this demonstration, the vibrational nodes within a baseball bat can be measured based on the ball’s contact with the ”sweet spot,” or the area on the barrel of the bat that induces the least amount of bat vibration. The project went through …


Asme 2020 Design Challenge, Anthony Acosta, Justine Alandy-Dy, Michael Lorberg, Nathan Vaska Dec 2019

Asme 2020 Design Challenge, Anthony Acosta, Justine Alandy-Dy, Michael Lorberg, Nathan Vaska

Mechanical Engineering Design Project Class

Our project was to build a machine that would fulfill the requirements for the ASME 2020 design challenge, which was called, ”Building to the Sky.” The rules of the challenge were to build a machine that would take ordinary 8.5” x 11” sheets of paper and stack them into a tower. To accomplish this task, we decided to make our paper tower out of accordion-shaped folds that would be placed on top of each other, alternating in 90 degree orientations. Our device is divided into various sub-components, each which manipulate the paper in various ways. We first have a mechanism …


Violin Prosthetic, Justin Kransdorf, Julia Rifkin, Hayden Reynolds, Payal Hukeri Dec 2019

Violin Prosthetic, Justin Kransdorf, Julia Rifkin, Hayden Reynolds, Payal Hukeri

Mechanical Engineering Design Project Class

Sam, an 11-year-old violin player was born without fingers or a thumb on his right hand. In order to learn the basics of violin, he currently uses a custom made prosthetic that allows him to hold a violin bow. However, his current prosthetic does not allow for the bow angle to change relative to his wrist, and thus, he cannot perform many techniques that are important to him furthering his violin skills. Specifically, his prosthetic allows Sam to use only a small percentage of the bow. For this project, a prosthetic was designed for Sam with the goal being to …


Automated Whiteboard Eraser, Trent Houpt, Tyler Polasek, Kenny Huang, Rocky Luo Dec 2019

Automated Whiteboard Eraser, Trent Houpt, Tyler Polasek, Kenny Huang, Rocky Luo

Mechanical Engineering Design Project Class

The Automated Whiteboard Eraser is a product designed to erase whiteboards with the touch of a button. With this product students and teachers will be able to save time and energy as they can continue to work without having to stop and erase. From our research others have attempted to construct similar products. We intend to improve these thoughts and designs in order to build a better and more efficient product.


Polyvinylpyrrolidone - Reduced Graphene Oxide - Pd Nanoparticles As An Efficient Nanocomposite For Catalysis Applications In Cross-Coupling Reactions, Hany A. Elazab, Tamer T. El-Idreesy Dec 2019

Polyvinylpyrrolidone - Reduced Graphene Oxide - Pd Nanoparticles As An Efficient Nanocomposite For Catalysis Applications In Cross-Coupling Reactions, Hany A. Elazab, Tamer T. El-Idreesy

Chemical Engineering

This paper reported a scientific approach adopting microwave-assisted synthesis as a synthetic route for preparing highly active palladium nanoparticles stabilized by polyvinylpyrrolidone (Pd/PVP) and supported on reduced Gra-phene oxide (rGO) as a highly active catalyst used for Suzuki, Heck, and Sonogashira cross coupling reactions with remarkable turnover number (6500) and turnover frequency of 78000 h-1. Pd/PVP nanoparticles supported on re-duced Graphene oxide nanosheets (Pd-PVP/rGO) showed an outstanding performance through high catalytic activ-ity towards cross coupling reactions. A simple, reproducible, and reliable method was used to prepare this efficient catalyst using microwave irradiation synthetic conditions. The synthesis approach requires simultaneous reduc-tion …


Hf Iq Mixer Vfo Temperature Compensation And Drive Level Optimization For Opposite Sideband Suppression, Katlin Anne-Rostomyan Dahn Dec 2019

Hf Iq Mixer Vfo Temperature Compensation And Drive Level Optimization For Opposite Sideband Suppression, Katlin Anne-Rostomyan Dahn

Dissertations and Theses

An amateur radio 40m band temperature compensated variable frequency oscillator (VFO) with drive-level optimized for opposite sideband suppression for use as the local oscillator (LO) of a high frequency (HF) IQ image reject mixer is considered in this work. The first problem of this thesis was the discovery of the HF IQ mixer's opposite sideband suppression dependence on LO drive-level. As a solution to this problem, the author built a fixed drive-level VFO for the optimal opposite sideband suppression. This then led to the second problem of this thesis; the discovery by this author of the well-known problem of VFO …


Board Erasing Device, Mark Fernandez, Christopher Sheffels, Joshua Miller Dec 2019

Board Erasing Device, Mark Fernandez, Christopher Sheffels, Joshua Miller

Mechanical Engineering Design Project Class

The Board Erasing Device is a portable automatic device designed to streamline a university lecturer’s board writing process by automatically erasing whiteboards while they are writing notes on adjacent boards. Our goal during this project was to design, build, and test a portable, automatic, and aesthetically pleasing device compatible with most standard whiteboards on Washington University in St. Louis’ Danforth campus. To that end, with a budget of $400, we created a prototype device to accomplish just that. Our prototype includes a felt eraser, pressed into the whiteboard via magnets. The eraser piece spans all eight feet of width on …


3d Chocolate Printer Dropper, Jessica Jimenez, Jacqueline Pielli, Shuhan Zhang Dec 2019

3d Chocolate Printer Dropper, Jessica Jimenez, Jacqueline Pielli, Shuhan Zhang

Mechanical Engineering Design Project Class

The Mechanical Engineering Department at Washington University in St. Louis is working to stimulate interest in the fields of fluid dynamics and thermal sciences, as students are not typically exposed to these topics within the first two years of school. Dr. Okamoto, Jeff Krampf, and Dr. Weisensee of the Mechanical Engineering Department would like to remedy this situation by developing a laboratory experiment for first year students that utilizes a 3D chocolate printer to teach thermal-fluid concepts in a fun and engaging manner. The goal of this project is to build a chocolate droplet dispensing system, which is a part …


Lidar Assessment To Monitor Bridge Response Under Live And Dead Loads, Daniel Watson Dec 2019

Lidar Assessment To Monitor Bridge Response Under Live And Dead Loads, Daniel Watson

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Understanding how a bridge structure responds to various loads in a time and resource-efficient approach is vital in characterizing bridge health. Bridge health monitoring is an evaluation of the structural condition and performance, which optimizes limited transportation budgets by prioritizing the bridges that are in the most need for retrofit or replacement. Identifying and remedying issues will mitigate long-term problems and ensure that the bridge remains open to service for all legal loads. In contrast, health monitoring and load rating will determine if a bridge can only carry traffic up to a certain weight or speed, requiring a bridge load …


Introducing Phonetic Information To Speaker Embedding For Speaker Verification, Yi Liu, Liang He, Michael T. Johnson Dec 2019

Introducing Phonetic Information To Speaker Embedding For Speaker Verification, Yi Liu, Liang He, Michael T. Johnson

Electrical and Computer Engineering Faculty Publications

Phonetic information is one of the most essential components of a speech signal, playing an important role for many speech processing tasks. However, it is difficult to integrate phonetic information into speaker verification systems since it occurs primarily at the frame level while speaker characteristics typically reside at the segment level. In deep neural network-based speaker verification, existing methods only apply phonetic information to the frame-wise trained speaker embeddings. To improve this weakness, this paper proposes phonetic adaptation and hybrid multi-task learning and further combines these into c-vector and simplified c-vector architectures. Experiments on National Institute of Standards and Technology …


Variable Camber Wings Using Compliant Mechanisms, Benjamin Moulton Dec 2019

Variable Camber Wings Using Compliant Mechanisms, Benjamin Moulton

Fall Student Research Symposium 2019

Wing morphing is the manipulation of a wing shape to influence aerodynamics. Wing morphing has significant aerodynamic advantages over traditional flaps, including increased efficiency and control. The USU Aerolab specializes in morphing aircraft and is currently working with the Air Force Research Lab on morphing straight wings [1-4].

The purpose of this project is to identify methods for applying morphing technologies to swept-wing aircraft. These methods are then used to create a morphing wing aircraft to demonstrate the efficiency and control of morphing flight with a swept wing.


2019 Fall Engr333 Poster, Megan Black, Evan Block, Jacob Deysher, Zach Erickson, Peter Atma, John Macy, Paul Steenwyk, Justin Skaggs, Justin Eekhoff, Adam Marquardt, Alan Samdel, Nathan Van Wyhe, Zach Ashenfelter, Brett Ermer, Clayton Lockwood, Ryan Schierbeek, Andrew Zerull, Matthew Buist, Hannah Chilkiewicz, Nathan Hall, Holly Straup, Ivy Chipinda, Andrew Huston, Peter Oh, Tony Vander Ploeg, Josh Hallenbeck, Cameron Ilbrink, Bridget Pertzsch, Lillie Spackman, Zuber Abdella, Michael Merz, Nathan Schuten, Abigail Willson, William Benneh, Marcus Gelder, Steven Vanast, Tyler Johnson, Christopher Pappageorge, Trevor Sando Dec 2019

2019 Fall Engr333 Poster, Megan Black, Evan Block, Jacob Deysher, Zach Erickson, Peter Atma, John Macy, Paul Steenwyk, Justin Skaggs, Justin Eekhoff, Adam Marquardt, Alan Samdel, Nathan Van Wyhe, Zach Ashenfelter, Brett Ermer, Clayton Lockwood, Ryan Schierbeek, Andrew Zerull, Matthew Buist, Hannah Chilkiewicz, Nathan Hall, Holly Straup, Ivy Chipinda, Andrew Huston, Peter Oh, Tony Vander Ploeg, Josh Hallenbeck, Cameron Ilbrink, Bridget Pertzsch, Lillie Spackman, Zuber Abdella, Michael Merz, Nathan Schuten, Abigail Willson, William Benneh, Marcus Gelder, Steven Vanast, Tyler Johnson, Christopher Pappageorge, Trevor Sando

ENGR 333

Energy efficiency can be a worthy goal for institutions and individuals; reducing energy consumption decreases demand for fossil fuels and consumes energy more sustainably. However, more cost-effective devices can lead to behavioral changes that ultimately increase energy consumption, even though the devices themselves are more energy efficient: This called the rebound effect. Rebound occurs when less energy is saved than expected. This can be a result of several factors: increased use of the device drawing more energy, manufacturers using more energy to create the new device, or money saved by the users being re-spent in the economy. The combination of …


Mazak Laser Optimization, Maylon Ellington, Terrilian E. Agbor Oji, William N. Palm Dec 2019

Mazak Laser Optimization, Maylon Ellington, Terrilian E. Agbor Oji, William N. Palm

Senior Design Project For Engineers

Starflex Fabrication is a manufacturing company that thrives to provide custom, precision fabricated parts, and assemblies to their customers.The Mazak laser is Starflex Fabrication’s primary cutting machine and is critical to the overall process for each order. Team Flex will look to optimize the laser’s process and improve overall shop throughput.


Hardware Implementation Of Assistive Technology Robot, Joycephine Li Dec 2019

Hardware Implementation Of Assistive Technology Robot, Joycephine Li

Publications and Research

SuperHERO is an on-going research project in Computer Engineering Technology department which involves upgrading Heathkit Education Robot (HERO) hardware circuits and features by using modern hardware devices and sensors. The current phase of the project will focus on upgrading the motor drive system hardware as well as implementation and testing of features such as mobile robot obstacle detection and other assistive technologies to help people with disabilities. This involves the reattachment of the robot arm after repairing and updating with 3D printing and using modern hardware and software technology. We observed that the robotic arm has rotary and translation movements …


Investigation Of Retrieved Cardiac Devices, Anmar Salih, Iosif Papadakis Ktistakis, Spyridon Manganas, Abdul Wase, Tarun Goswami Dec 2019

Investigation Of Retrieved Cardiac Devices, Anmar Salih, Iosif Papadakis Ktistakis, Spyridon Manganas, Abdul Wase, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Damage assessment of lead and pulse generator with various exposure times is important in the development of cardiac devices. Approximately, 92.1 million patients in the US suffer from cardiovascular diseases with an estimated healthcare cost of over $300 billion and at least one million with implantable cardiac devices. These devices are complex and composed on multiple levels and present challenges while assessing the damage. However, the study on the analysis of cardiac devices may lend insight into common damage patterns and improve future cardiac devices design. The objective of this work is to perform a thorough in vivo damage assessment …


Amodal Instance Segmentation And Multi-Object Tracking With Deep Pixel Embedding, Yanfeng Liu Dec 2019

Amodal Instance Segmentation And Multi-Object Tracking With Deep Pixel Embedding, Yanfeng Liu

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

This thesis extends upon the representational output of semantic instance segmentation by explicitly including both visible and occluded parts. A fully convolutional network is trained to produce consistent pixel-level embedding across two layers such that, when clustered, the results convey the full spatial extent and depth ordering of each instance. Results demonstrate that the network can accurately estimate complete masks in the presence of occlusion and outperform leading top-down bounding-box approaches.

The model is further extended to produce consistent pixel-level embeddings across two consecutive image frames from a video to simultaneously perform amodal instance segmentation and multi-object tracking. No post-processing …


Diver Propulsion Wearable, Joseph Lucca Paletta, Andrew Kessler, Andrew Beukelman, Nico Topulos Dec 2019

Diver Propulsion Wearable, Joseph Lucca Paletta, Andrew Kessler, Andrew Beukelman, Nico Topulos

Mechanical Engineering Design Project Class

This project was proposed by Jin Hwan (Josh) An, a current undergraduate student in the Olin Business School at Washington University in St Louis. Given his interest in diving and his experience with current diver propulsion vehicles, Josh has challenged us to design a hands-free diver propulsion wearable (DPW). While Josh has left the project rather open-ended for the engineers, the main challenge is to create a design that can propel the diver using a hands-free control system. Having a hands-free controller will allow the user to engage in other tasks while gliding underwater. Ideally, this design would be useful …


Space Optimization And Process Improvement, Harith Alshareef Dec 2019

Space Optimization And Process Improvement, Harith Alshareef

Senior Design Project For Engineers

Siemens Energy warehouse located in Suwanee, GA runs out of space in the Precision Lab due to rapid growth, seasonal peaks, and poor space utilization. The objective of the project is to redesign the Precision Lab layout and improve the tool assessment process to increase efficiency, productivity, and profitability.

The first solution is to add shelves in the Precision lab as well as the Torque lab and reduce the honeycombing effect on the shelves, which results in a 120%-150% increase in the storage space. We propose adding Tablets that include barcode scanner features to reduce the time spent on the …


Design Of The Skybus Sb-400 High Capcity Short Range Transport Aircraft, Alexander Barroso, Austin Klee, Chandler Palmer Dec 2019

Design Of The Skybus Sb-400 High Capcity Short Range Transport Aircraft, Alexander Barroso, Austin Klee, Chandler Palmer

Senior Design Project For Engineers

As air travel becomes more and more affordable and the world economy expands, so does the demand for flights. Major commercial airports and their infrastructure are struggling to keep up with this increased demand. The AIAA has identified this problem and has put out a Request for Proposal for a High Density Short Range Transport Aircraft which can carry 400 people in a two class configuration up to 3,500 nautical miles. The Skybus SB-400 is our clean slate design response to the AIAA’s RFP for a High DensityShort Range Transport Aircraft. an increasing part of everyday life. Our focus for …


Forensic Investigation Of Building Failure – The Harbour Cay Condominium Disaster, John Airis Dec 2019

Forensic Investigation Of Building Failure – The Harbour Cay Condominium Disaster, John Airis

Publications and Research

When a building suffers collapse, the U.S. Occupational Safety and Health Administration (OSHA) is tasked with conducting an investigation into the cause. Often OSHA will request technical assistance from the National Institute for Standards and Technology to assist in the forensic technical aspects determining a most probable cause. This forensic effort entails many actions. The Harbour Cay Condominium disaster occurred on March 28, 1981 in Cocoa Beach, Florida. It was a total collapse of a five story reinforced concrete structure during the last stage of roof construction, resulting in 11 deaths and 24 injuries. The investigation report revealed structural design …


Optimal Allocation Of Energy Storage And Wind Generation In Power Distribution Systems, Carlos Mendoza Dec 2019

Optimal Allocation Of Energy Storage And Wind Generation In Power Distribution Systems, Carlos Mendoza

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The advent of energy storage technologies applications for the electric power system gives new tools for planners to cope with the operation challenges that come from the integration of renewable generation in medium voltage networks. This work proposes and implements an optimization model for Battery Energy Storage System (BESS) and distributed generation allocation in radial distribution networks. The formulation aims to assist distribution system operators in the task of making decisions on energy storage investment, BESSs' operation, and distributed generation penetration's level to minimize electricity costs. The BESSs are required to participate in energy arbitrage and voltage control. In addition, …


Metal-Free Deep Eutectic Solvents: Preparation, Physical Properties, And Significance, Burcu E. Gurkan, Henry Squire Dec 2019

Metal-Free Deep Eutectic Solvents: Preparation, Physical Properties, And Significance, Burcu E. Gurkan, Henry Squire

Faculty Scholarship

In the past decade, reports detailing the preparation, characterization, and application of deep eutectic solvents (DESs) have grown in number significantly, showing signs of increased interest and attention. Indeed, these systems provide tunable polar environments attractive for their ease of synthesis and lack of need for purification. DESs are homogeneous systems composed of two or more components having a significantly depressed melting point compared to either constituent material. As interest and application of DESs grow, the need for a common understanding of their preparation and characterization is required. In this Perspective, we discuss metal-free DESs, focusing on their preparation, characterization …