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Full-Text Articles in Materials Science and Engineering

Evaluation And Update Of Mash Test Vehicles, Kellon B. Ronspies Apr 2020

Evaluation And Update Of Mash Test Vehicles, Kellon B. Ronspies

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The Manual for Assessing Safety Hardware (MASH) requires full-scale crash testing of roadside features using worst practical impact conditions. Vehicle selection for full-scale crash testing is intended to be representative of the contemporary passenger vehicle fleet. Researchers at the Midwest Roadside Safety Facility (MwRSF) investigated attributes of passenger vehicle sales to determine if the vehicle selection criteria shown in MASH should be revised to accommodate changes in the vehicle fleet. A methodology was considered to affordably re-analyze the vehicle fleet when necessary to ensure MASH vehicle selection criteria are reflective of vehicles currently on roadways.

Representative vehicles were documented using …


Designing An Adjustable And Transportable Staircase, Allison Currey Apr 2020

Designing An Adjustable And Transportable Staircase, Allison Currey

Undergraduate Honors Thesis Projects

People climb stairs every day, whether it is at work, a store, or at home; however, there are populations such as people who are elderly, with pathologies, with Parkinson’s disease, or have suffered from a stroke that see climbing the stairs as a challenging task and it decreases their mobility and quality of life. Factors such as muscle weakness, strategy, and balance have been previously investigated in these populations during stair climbing. However, few studies have researched how stair climb ability, balance, and perception of difficulty are influenced by step height. The objective of this thesis is to design a …


Faculty Instruction Face Shield Project, David Holden, John Schneiderhan Apr 2020

Faculty Instruction Face Shield Project, David Holden, John Schneiderhan

Michigan Tech 3D Designs

Early in the spring of 2020 project contributors David Holden and John Schneiderhan began test printing a variety of open source Personal Protective Equipment (PPE)/Covid related items that could help protect or prevent the spread of the emerging virus. With assistance from Pete Baril of the Western Upper Peninsula Health Department (WUPHD) approval was obtained for the face shields to be used in the health care and nursing homes in the area. With the support and approval from university and library administration efforts were coordinated with Dr. Joshua Pearce and the students from the MOST lab to concentrate on the …


On-Chip Terahertz Modulation And Emission With Integrated Graphene Junctions, Joshua O. Island, Peter Kissin, Jacob Schalch, Xiaomeng Cui, Sheikh Rubaiat Ui Haque, Alex Potts, Takashi Taniguchi, Kanji Watanabe, Richard D. Averitt, Andrea F. Young Apr 2020

On-Chip Terahertz Modulation And Emission With Integrated Graphene Junctions, Joshua O. Island, Peter Kissin, Jacob Schalch, Xiaomeng Cui, Sheikh Rubaiat Ui Haque, Alex Potts, Takashi Taniguchi, Kanji Watanabe, Richard D. Averitt, Andrea F. Young

Physics & Astronomy Faculty Research

The efficient modulation and control of ultrafast signals on-chip is of central importance in terahertz (THz) communications and a promis- ing route toward sub-diffraction limit THz spectroscopy. Two-dimensional (2D) materials may provide a platform for these endeavors. We explore this potential, integrating high-quality graphene p–n junctions within two types of planar transmission line circuits to modulate and emit picosecond pulses. In a coplanar strip line geometry, we demonstrate the electrical modulation of THz signal transmission by 95%. In a Goubau waveguide geometry, we achieve complete gate-tunable control over THz emission from a photoexcited graphene junction. These studies inform the development …


Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson Apr 2020

Thermal Modeling Of Additive Manufacturing Using Graph Theory: Validation With Directed Energy Deposition, Jordan Severson

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Metal additive manufacturing (AM/3D printing) offers unparalleled advantages over conventional manufacturing, including greater design freedom and a lower lead time. However, the use of AM parts in safety-critical industries, such as aerospace and biomedical, is limited by the tendency of the process to create flaws that can lead to sudden failure during use. The root cause of flaw formation in metal AM parts, such as porosity and deformation, is linked to the temperature inside the part during the process, called the thermal history. The thermal history is a function of the process parameters and part design.

Consequently, the first step …


Laser Micropatterning Effects On Corrosion Resistance Of Pure Magnesium Surfaces, Yahya Efe Yayoglu Apr 2020

Laser Micropatterning Effects On Corrosion Resistance Of Pure Magnesium Surfaces, Yahya Efe Yayoglu

USF Tampa Graduate Theses and Dissertations

Magnesium and its alloys are good candidates to manufacture medical implants. They have excellent biocompatibility and because they biodegrade secondary surgical operation to remove the implant could be eliminated. However, in aqueous environments, magnesium alloys rapidly corrode, resulting in premature degradation of the implant along with biologically intolerable hydrogen gas generation. In literature, there are multiple studies focused on creating water repelling hydrophobic magnesium surfaces in order to decrease corrosion rates. Hydrophobic properties can be achieved by creation of a roughness profile on an initially smooth surface combined with a treatment that reduces the free surface energy. In theory, hydrophobic …


Mid-Ir Optical Refrigeration And Radiation Balanced Lasers, Saeid Rostami Apr 2020

Mid-Ir Optical Refrigeration And Radiation Balanced Lasers, Saeid Rostami

Optical Science and Engineering ETDs

This dissertation reports recent advances in mid-infrared (mid-IR) optical refrigeration and Radiation Balanced Lasers (RBLs). The first demonstration of optical refrigeration in Ho:YLF and Tm:YLF crystals as promising mid-IR laser cooling candidates is reported. Room temperature laser cooling efficiency of Tm- and Ho-doped crystals at different excitation polarization is measured and their external quantum efficiency and background absorption are extracted. Complete characterization of laser cooling samples is obtained via performing detailed low-temperature spectroscopic analysis, and their minimum achievable temperature as well as conditions to achieve laser cooling efficiency enhancement in mid-IR are investigated. By developing a Thulium-doped fiber amplifier, seeded …


Quantifying Wicking In Functionlized Surfaces, Maureen Winter, Ryan Regan, Alfred Tsubaki, Craig Zuhlke, Dennis Alexander, George Gogos Apr 2020

Quantifying Wicking In Functionlized Surfaces, Maureen Winter, Ryan Regan, Alfred Tsubaki, Craig Zuhlke, Dennis Alexander, George Gogos

UCARE: Research Products

Wicking remains the enigmatic key factor in many research areas. From boiling in power plants, to anti-icing on plane wings, to medical instruments, to heat pipes, efficiency and safety depend on how quickly a surface becomes wet. Yet wicking remains difficult to quantify and define as a property of the surface. This experiment strives to measure the wicking property by examining the rate that a liquid can be pulled out of a container. A superhydrophilic surface is placed in contact with the liquid at the bottom of a tube so that the volume flow rate across the surface can be …


Growth And Characterization Of 2d Layered Materials, Algene Fryer Ii Apr 2020

Growth And Characterization Of 2d Layered Materials, Algene Fryer Ii

USF Tampa Graduate Theses and Dissertations

2D layered materials are becoming an important area of research due to their exceptional electrical and optical properties. Specifically, 2D layered monochalcogenides are known for their high carrier motilities, whereas layered metal halides have been shown to have noteworthy photoresponsivity. Despite the assortment of 2D layered materials, the search for reliable and scalable synthesis methods is still a challenge in this family of materials. Often a certain growth technique will compromise a desirable trait needed for further fabrication, such as the quality of the crystal or its coverage on a substrate. In this study, two growth techniques that incorporate changeable …


Mitigating Safety Concerns And Profit/Production Losses For Chemical Process Control Systems Under Cyberattacks Via Design/Control Methods, Helen Durand, Matthew Wegener Apr 2020

Mitigating Safety Concerns And Profit/Production Losses For Chemical Process Control Systems Under Cyberattacks Via Design/Control Methods, Helen Durand, Matthew Wegener

Chemical Engineering and Materials Science Faculty Research Publications

One of the challenges for chemical processes today, from a safety and profit standpoint, is the potential that cyberattacks could be performed on components of process control systems. Safety issues could be catastrophic; however, because the nonlinear systems definition of a cyberattack has similarities to a nonlinear systems definition of faults, many processes have already been instrumented to handle various problematic input conditions. Also challenging is the question of how to design a system that is resilient to attacks attempting to impact the production volumes or profits of a company. In this work, we explore a process/equipment design framework for …


Loading Orientation Dependence On The Compressive Response Of Ice-Templated Ceramic-Polymer Composites, Sashanka Akurati, Justine Marin, Dipankar Ghosh Apr 2020

Loading Orientation Dependence On The Compressive Response Of Ice-Templated Ceramic-Polymer Composites, Sashanka Akurati, Justine Marin, Dipankar Ghosh

College of Engineering & Technology (Batten) Posters

Natural materials are made from weak constituents, yet exhibit an excellent synergy of high stiffness, strength, and damage-tolerance. They consist of alternate layers of the hard and soft phases with a complex hierarchical structural organization. The ice-templating technique provides an approach to fabricate multilayered architectures for engineering applications. In this technique, an aqueous ceramic suspension is solidified unidirectionally leading to phase separation into alternating layers of ice-crystals and ceramic particles. Ice-crystals are sublimated by freeze-drying process and resultant ceramic foams are sintered to impart strength. The fabricated sintered ceramic foams contain alternate layers of oriented ceramic lamella walls and pores. …


Questaal: A Package Of Electronic Structure Methods Based On The Linear Muffin-Tin Orbital Technique, Dimitar Pashov, Swagata Acharya, Walter R.L. Lambrecht, Jerome Jackson, Kirill Belashchenko, Athanasios Chantis, Francois Jamet, Mark Van Schilfgaarde Apr 2020

Questaal: A Package Of Electronic Structure Methods Based On The Linear Muffin-Tin Orbital Technique, Dimitar Pashov, Swagata Acharya, Walter R.L. Lambrecht, Jerome Jackson, Kirill Belashchenko, Athanasios Chantis, Francois Jamet, Mark Van Schilfgaarde

Kirill Belashchenko Publications

This paper summarises the theory and functionality behind Questaal, an open-source suite of codes for calculating the electronic structure and related properties of materials from first principles. The formalism of the linearised muffin-tin orbital (LMTO) method is revisited in detail and developed further by the introduction of short-ranged tight-binding basis functions for full-potential calculations. The LMTO method is presented in both Green's function and wave function formulations for bulk and layered systems. The suite's full-potential LMTO code uses a sophisticated basis and augmentation method that allows an efficient and precise solution to the band problem at different levels of theory, …


Morphology And Structure Of Pb Thin Films Grown On Si (111) By Pulsed Laser Deposition, Bektur Abdisatarov Apr 2020

Morphology And Structure Of Pb Thin Films Grown On Si (111) By Pulsed Laser Deposition, Bektur Abdisatarov

Masters Theses & Specialist Projects

Pulsed laser deposition (PLD) is a versatile thin film deposition technique in which high powered laser beam interacts with a target material inside an ultrahigh vacuum chamber. Highly energetic particles such as electrons, atoms, protons, and ions generate a plasma plume that directed towards a substrate material where recondenses form a thin film. PLD is an effective and reliable method to create varieties of thin films such as metal, polymer, and ceramic for many technologically essential applications.

In this study, thin Pb films were grown by pulsed laser deposition on Si (111) at various laser fluences, pulse wavelengths, deposition times, …


Synthesis Of Sic Resin For 3d Printing Of Sic Ceramics By Digital Light Processing, Kevin Zhao, Bai Cui Apr 2020

Synthesis Of Sic Resin For 3d Printing Of Sic Ceramics By Digital Light Processing, Kevin Zhao, Bai Cui

UCARE: Research Products

Silicon carbide (SiC) resin is produced through shear mixing 0.1-1 μm SiC powders with Tethon’s high load Genesis resin base. Resins of varying SiC vol.% were synthesized to test the loading limit of the resin base; 10, 20, and 30 vol.% of SiC were made with the resin base handling the higher loads quite well. Several attempts were made at printing using the Tethon Bison 1000 DLP printer with higher loads of SiC showing better results even with lower intensity UV lights andtimes.


Defect Characterization Of Additively Manufactured Parts, Sabrina D'Alesandro, Joy Gockel, Andrew Harvey Apr 2020

Defect Characterization Of Additively Manufactured Parts, Sabrina D'Alesandro, Joy Gockel, Andrew Harvey

Celebration of Undergraduate & Graduate Research, Scholarship, and Creative Activities Materials

This document describes various image processing techniques to be used for defect characterization of additively manufactured parts. This will help the reader gain knowledge of materials science engineering and the nuances in analyzing data from image processing software.

Additive manufacturing is shaping the manufacturing world through simplistic household printers’ to more complex metal printers used for a variety of applications. Specifically, laser powder bed fusion (LPBF) is an additive manufacturing process that deposits metal powder over the build plate and melts it with a laser in the shape of the build part. In order to make LPBF more efficient with …


A Novel Method For Making Titanium Dioxide For Photocatalytic Applications, Gary Wilson Apr 2020

A Novel Method For Making Titanium Dioxide For Photocatalytic Applications, Gary Wilson

Graduate Theses & Non-Theses

Titanium dioxide possesses near-ideal properties for large-scale application as a photocatalyst. It is cheap and abundant, nontoxic, and environmentally safe. However, it still suffers from logistical problems preventing its application in industry: namely, rapid electron-hole recombination and inability to utilize visible light. For nearly five decades researchers in this booming field have made numerous attempts to address these problems, doping and combining titanium dioxide with a wide range of materials. A novel ambient-temperature approach to synthesis and doping/modification of anatase-form titanium dioxide was attempted using both oxygen-rich and oxygen deprived synthetic routes. Reactants were exposed to various wavelengths of ultraviolet …


Correction To: Recommendations Of Rilem Tc 260-Rsc For Using Superabsorbent Polymers (Sap) For Improving Freeze–Thaw Resistance Of Cement-Based Materials (Materials And Structures, (2019), 52, 4, (75), 10.1617/S11527-019-1375-4), Viktor Mechtcherine, Christof Schröfl, Michaela Reichardt, Agnieszka J. Klemm, Kamal Khayat Apr 2020

Correction To: Recommendations Of Rilem Tc 260-Rsc For Using Superabsorbent Polymers (Sap) For Improving Freeze–Thaw Resistance Of Cement-Based Materials (Materials And Structures, (2019), 52, 4, (75), 10.1617/S11527-019-1375-4), Viktor Mechtcherine, Christof Schröfl, Michaela Reichardt, Agnieszka J. Klemm, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Agnieszka J. Klemm is affiliated to Glasgow Caledonian University, Glasgow, UK.


Estimation Of Lubrication Layer Thickness And Composition Through Reverse Engineering Of Interface Rheometry Tests, Alexis Salinas, Dimitri Feys Apr 2020

Estimation Of Lubrication Layer Thickness And Composition Through Reverse Engineering Of Interface Rheometry Tests, Alexis Salinas, Dimitri Feys

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

During concrete pumping, a lubrication layer is formed near the pipe wall. Extensive research has been performed on measuring and modeling the properties of this layer and using these values to predict pumping pressures. However, there are numerous discussions in the literature about the composition and thickness of this layer: can it be considered mortar, a micromortar, or is it cement paste? In this paper, possible solutions for the thickness and composition of the lubrication layer are derived from interface rheometry tests. It is assumed that the lubrication layer is composed of one or more concentric layers of paste or …


Investigation Of Selective Laser Melting Fabricated Internal Cooling Channels, Colin Jack Apr 2020

Investigation Of Selective Laser Melting Fabricated Internal Cooling Channels, Colin Jack

Masters Theses

Channels where coolant is run to cool a system are common in injection mold tooling. Conventionally, these channels are machined into the mold. This has limited the design of mold cooling systems to the constraints of traditional machining processes, where straight circular channels machined from cast material are typical. The transfer of heat away from the part cavity into these cooling channels has a large effect on the cooling time of the injection mold cycle. In this investigation, laser powder bed fusion processes were used to create non-circular cooling channels. To compare cooling performance, elliptical and circular channels of equal …


Effect Of Frother Strength And Solids On Gas Dispersion In A Cavitation Sparger Measured By Electrical Resistance Tomography, Philip Holdsworth Apr 2020

Effect Of Frother Strength And Solids On Gas Dispersion In A Cavitation Sparger Measured By Electrical Resistance Tomography, Philip Holdsworth

Graduate Theses & Non-Theses

Gas dispersion in column flotation is critical for optimizing particle-bubble interaction and maximizing recovery. The effect of various flotation frothers on axial gas dispersion rates in a column flotation cell were measured using electrical resistance tomography (ERT). Tests included two-phase (gas-liquid) and three-phase (gas-liquid-solid) to determine the effect of mechanical parameters and the presence of solids on gas dispersion. Gas holdup can be measured using ERT and utilized in the determination of axial gas dispersion rate in the column. The ERT is constructed with two sensor planes making it possible to simultaneously capture gas holdup values at one cm and …


Cellulose Based Separator For High-Performance Lithium-Ion Batteries, Akshit Vaidya Apr 2020

Cellulose Based Separator For High-Performance Lithium-Ion Batteries, Akshit Vaidya

Masters Theses

During the past two decades, lithium-ion batteries (LIBs) have gained great success in the field of portable devices, and currently, are penetrating to the market of vehicles. Compared to the fast development of LIBs, little efforts have been dedicated to the separator, which is one of the most important components of LIBs. Primarily, the lithium-ion battery separator has two functions, one is to prevent direct contact between the positive and negative electrodes, and the other is to provide a path for effective ionic transportation. Currently, the separator market of LIBs is dominated by polyolefin materials such as polypropylene, polyethylene, and …


Enhanced Carrier Transport By Transition Metal Doping In Ws2 Field Effect Transistors, Maomao Liu, Sichen Wei, Simran Shahi, Hemendra Nath Jaiswal, Paolo Paletti, Sara Fathipour, Maja Remskar, Jun Jiao, Wansik Hwang, Fei Yao, Huamin Li Apr 2020

Enhanced Carrier Transport By Transition Metal Doping In Ws2 Field Effect Transistors, Maomao Liu, Sichen Wei, Simran Shahi, Hemendra Nath Jaiswal, Paolo Paletti, Sara Fathipour, Maja Remskar, Jun Jiao, Wansik Hwang, Fei Yao, Huamin Li

Physics Faculty Publications and Presentations

High contact resistance is one of the primary concerns for electronic device applications of two-dimensional (2D) layered semiconductors. Here, we explore the enhanced carrier transport through metal–semiconductor interfaces in WS2 field effect transistors (FETs) by introducing a typical transition metal, Cu, with two different doping strategies: (i) a “generalized” Cu doping by using randomly distributed Cu atoms along the channel and (ii) a “localized” Cu doping by adapting an ultrathin Cu layer at the metal–semiconductor interface. Compared to the pristine WS2 FETs, both the generalized Cu atomic dopant and localized Cu contact decoration can provide a Schottky-to-Ohmic contact …


Verification Of Effectiveness Of Spot-Heating Technique In Reducing Spread Of Weld Lines In Injection Molded Plastic Products, Shah Ashikul Abed Sakar Apr 2020

Verification Of Effectiveness Of Spot-Heating Technique In Reducing Spread Of Weld Lines In Injection Molded Plastic Products, Shah Ashikul Abed Sakar

Masters Theses

In producing a plastic part in an injection molding machine many physical factors related to the machine, such as injection pressure, holding pressure, heater temperature, etc. play their roles in the overall quality of the produced part. There are many aspects of the quality of a plastic part, such as part strength, part dimensions, and part surface finish. If any of those aspects gets compromised, the part is considered to have some defects. Of all defects found in injection-molded plastic parts, one most common defect is the presence of weld lines.Weld lines are formed when the flow of the molten …


Effects Of Collision Damage On The Ultimate Strength Of Fpso Vessels, Muhammad Zubair Muis Alie, Dian Ramasari, Taufiqur Rachman, Ristiyanto Adiputra Apr 2020

Effects Of Collision Damage On The Ultimate Strength Of Fpso Vessels, Muhammad Zubair Muis Alie, Dian Ramasari, Taufiqur Rachman, Ristiyanto Adiputra

Makara Journal of Technology

Floating production storage offloading (FPSO) vessels are movable offshore structures. These structures are designed with large dimensions, and their decks are loaded with several types of equipment. During collision damage, the hull and deck parts loaded with equipment are severely affected. Therefore, the ultimate strength of FPSO vessels should be thoroughly checked and evaluated. The objective of the present study is to analyze the ultimate strength of FPSO vessels against collision damage characterized by hogging and sagging under longitudinal bending. The cross section of an FPSO vessel is modeled with elements composed of stiffened and unstiffened plates. The vessel length …


Ionic Conductivity And Electrochemical Properties Of Alginate–Nn4no3-Based Biopolymer Electrolytes For Edlc Application, Norfatihah Binti Mazuki, Nur Muhitul Jalilah Rasali, Bouchta Sahraoui, Ahmad Salihin Samsudin Apr 2020

Ionic Conductivity And Electrochemical Properties Of Alginate–Nn4no3-Based Biopolymer Electrolytes For Edlc Application, Norfatihah Binti Mazuki, Nur Muhitul Jalilah Rasali, Bouchta Sahraoui, Ahmad Salihin Samsudin

Makara Journal of Technology

In this work, alginate doped with various contents of ammonium nitrate (NH4NO3) as a solid biopolymer electrolyte (SBE) was prepared via casting by using distilled water as a solvent. Impedance studies on alginate–NH4NO3 SBE films were conducted via impedance spectroscopy. The lowest bulk resistance (Rb) showed that the maximum ionic conductivity of the sample containing 25 wt.% NH4NO3 at ambient temperature (303 K) was 5.56 × 10−5 S cm−1. The temperature dependence of ionic conductivity was evaluated, and results confirmed that electrolytes followed an Arrhenius behavior. The highest conducting sample was fabricated into an electrical double-layer capacitor and characterized in …


Synthesis Of Epoxy Monoethanolamide From Bauhinia Monandra Seed Oil, Adewale Adewuyi, Rotimi A. Oderinde Apr 2020

Synthesis Of Epoxy Monoethanolamide From Bauhinia Monandra Seed Oil, Adewale Adewuyi, Rotimi A. Oderinde

Makara Journal of Technology

In this study, we synthesized epoxidised monoethanolamide (EMA) from Bauhinia monandra seed oil (BMO) via a simple reaction route. In this process, BMO was transesterified to obtain a mixture of methyl esters, which was subjected to a urea adduct complexation reaction. The unsaturated methyl esters (BME) from the urea adduct complexation reaction were then epoxidised using performic acid produced in situ in a one-pot reaction system. The epoxidised methyl esters were converted to EMA by reacting them with monoethanolamine (1:10). The progression of the reaction was monitored using Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, and the …


Parametric Investigation Of Effect Of Abnormal Process Conditions On Self-Piercing Riveting, Taek-Eon Jeong, Dong-Hyuck Kam, Cheolhee Kim Apr 2020

Parametric Investigation Of Effect Of Abnormal Process Conditions On Self-Piercing Riveting, Taek-Eon Jeong, Dong-Hyuck Kam, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

Self-piercing riveting (SPR) is one of the mechanical joining processes, and its application to Al/Fe dissimilar materials combination, which is hard to weld, is expanding in the automotive industry. The main process parameters in SPR are types of rivet and die, setting force, and rivet setting speed. Previously, the relationship between the main process parameters and output parameters such as cross-sectional characteristics and joint strength has been studied to optimize the SPR process. In practical applications, there are unexpected and abnormal process conditions such as poor fit-up, angular misalignment, edge offset distance, and inaccurate setting and pre-clamping forces, and their …


Ethylene Carbonate And Polyethylene Glycol As Efficient Plasticizers In Cmc-Pva-Nh4no3-Based Polymer Electrolyte, Noor Saadiah Mohd Ali, Yuki Nagao, Ahmad Salihin Samsudin Apr 2020

Ethylene Carbonate And Polyethylene Glycol As Efficient Plasticizers In Cmc-Pva-Nh4no3-Based Polymer Electrolyte, Noor Saadiah Mohd Ali, Yuki Nagao, Ahmad Salihin Samsudin

Makara Journal of Technology

This study investigated the influence of plasticizers (polyethylene glycol [PEG] and ethylene carbonate [EC]) on the ionic conduction of CMC-PVA-NH4NO3. Blended biopolymer electrolytes (BBEs) based on carboxymethyl cellulose–polyvinyl alcohol (CMC-PVA) doped with ammonium nitrate (NH4NO3) were obtained via casting solution technique incorporated with PEG and EC, which acted as plasticizers. Electrical impedance spectroscopy (EIS) was conducted to evaluate the effect of plasticization on the ionic conduction properties. The ionic conductivity improved from 1.70 × 10−3 S/cm for un-plasticized BBEs to 3.92 × 10−3 S/cm for plasticized BBEs with EC and 3.00 × 10−3 S/cm for plasticized BBEs with PEG. The …


Current Status Of Hydrothermal Treatment For Energy And Material Recovery Toward A Sustainable Post-Consumer Material Cycle, Baskoro Lokahita, Muhammad Aziz, Fumitake Takahashi Apr 2020

Current Status Of Hydrothermal Treatment For Energy And Material Recovery Toward A Sustainable Post-Consumer Material Cycle, Baskoro Lokahita, Muhammad Aziz, Fumitake Takahashi

Makara Journal of Technology

The demand for energy-efficient and environmentally friendly municipal solid waste (MSW) processing has increased in developing countries. The thermochemical process offers a fast and reliable solution to reutilize or reduce the volume of MSW. Hydrothermal treatment is a novel MSW treatment technology that is compatible with high-moisture-content feedstock. It involves the thermal degradation of MSW in pressurized water or steam, which promotes the disintegration of cellulosic and polymer materials. Recent advances have shown effective MSW conversion into homogenous solid hydrochar with higher energy density. Alkali and chlorine content, which causes issues in combustors, was successfully removed due to the washing …


Liquefaction Potential Analysis Based On Nonlinear Ground Response On The Coastline Of Bengkulu City, Indonesia, Lindung Zalbuin Mase Apr 2020

Liquefaction Potential Analysis Based On Nonlinear Ground Response On The Coastline Of Bengkulu City, Indonesia, Lindung Zalbuin Mase

Makara Journal of Technology

This paper presents the study of the seismic response and liquefaction potential of the coastal area of Bengkulu City during the September 2007 Sumatra earthquake. The study is conducted by collecting site investigation data (standard penetration test) and applying input motion to observe soil response. Synthetic ground motion is generated by considering the important aspects of earthquakes, including focal depth, epicenter, earthquake source, and site classification. The synthetized ground motion is then used as the input motion in the seismic response analysis. The results of this analysis are spectral acceleration and peak ground acceleration at each depth. The resulting spectral …