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Full-Text Articles in Materials Science and Engineering

Supercapacitors From Nitrogen And Sulfur Co-Doped Graphene/Nickel Cobalt Sulfide, Nutthapong Poompiew Jan 2021

Supercapacitors From Nitrogen And Sulfur Co-Doped Graphene/Nickel Cobalt Sulfide, Nutthapong Poompiew

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research aims to develop high performance supercapacitors in term of capacitive efficiency, power density and long-term cycle stability. Supercapacitors are a kind of energy storages device which exhibit high power density when comparing with conventional batteries. However, most of them exhibits inefficient energy capacitance and long-term cycle stability. Thus, this research is focusing on development materials for using as supercapacitor electrodes. Thus, nitrogen and sulfur co-doped graphene and nickel cobalt compounds were synthesized using in situ hydrothermal process. This research is divided into two major parts (i) to sort out the optimum ratio of nickel and cobalt for the …


การเตรียมเซรามิกเซอร์โคเนียความหนาแน่นสูงจากเศษเจียระไนคิวบิกเซอร์โคเนีย, ณัชชา ปาลวัฒน์ Jan 2021

การเตรียมเซรามิกเซอร์โคเนียความหนาแน่นสูงจากเศษเจียระไนคิวบิกเซอร์โคเนีย, ณัชชา ปาลวัฒน์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ในแต่ละปีอุตสาหกรรมเจียระไนเครื่องประดับคิวบิกเซอร์โคเนียในประเทศไทยมีปริมาณเศษเจียระไนคิวบิกเซอร์โคเนียปริมาณมากหลายร้อยตันถูกทิ้งอย่างสูญเปล่า จึงเกิดแนวคิดในการศึกษาวิจัยเพื่อพัฒนากระบวนการผลิตเซรามิกเซอร์โคเนียความหนาแน่นสูงโดยใช้เศษเจียระไนคิวบิกเซอร์โคเนียจากอุตสาหกรรมเป็นวัตถุดิบหลักในการทดลอง ร่วมกับการใช้สารตัวเติมแคลเซียมไดไฮโดรเจนฟอสเฟตเพื่อช่วยทำให้โครงสร้างเกิดเฟสของเหลวในขั้นตอนการเผาผนึก โดยทำการเตรียมตัวอย่างจากการนำเศษเจียระไนมาผ่านการเผาแคลไซน์ที่อุณหภูมิ 1000 องศาเซลเซียส เป็นเวลา 1 ชั่วโมง เพื่อกำจัดสิ่งเจือปนที่มาจากขั้นตอนการผลิตเครื่องประดับ ก่อนนำไปทำการบดผสมกับแคลเซียมไดไฮโดรเจนฟอสเฟตในอัตราส่วนร้อยละ 5 และ 10 โดยน้ำหนัก บดผสมเป็นเวลา 24 และ 48 ชั่วโมง จากนั้นนำไปอัดขึ้นรูปที่ความดัน 50 MPa เพื่อให้ได้ชิ้นงานที่มีลักษณะเป็นแผ่นกลมขนาดเส้นผ่านศูนย์กลาง 20 mm และนำไปเผาผนึกที่อุณหภูมิ 1650 องศาเซลเซียส เป็นเวลา 1, 2 และ 4 ชั่วโมง และแบ่งการศึกษาเป็นการเปรียบเทียบการเผาผนึกแบบสถานะของแข็งที่ไม่มีการใช้เติมสารตัวเติม และการเผาผนึกแบบเฟสของเหลวที่มีการเติมสารตัวเติมช่วยในการเผาผนึก โดยจากผลการทดลองพบว่าเงื่อนไขที่ดีที่สุด คือ ชิ้นงานที่ผ่านกระบวนการบดผสมกับสารตัวเติมในอัตราส่วนร้อยละ 10 โดยน้ำหนัก บดผสมเป็นเวลา 24 ชั่วโมง และเผาผนึกเป็นเวลา 2 ชั่วโมง พบว่าได้ค่าความหนาแน่นสูงถึง 5.27 g/cm3 ค่าการดูดซึมน้ำร้อยละ 0.12 และมีค่าความแข็ง 6.72 GPa ดังนั้นจึงทำการเลือกเงื่อนไขนี้มาเตรียมเป็นชิ้นงานแท่งสี่เหลี่ยมขนาด 60x10x5 mm เพื่อนำไปทดสอบความแข็งแรงด้วยเทคนิค 3-point bending จากผลการทดสอบพบว่าค่าความต้านทานแรงดัดมีค่าเท่ากับ 90.66 MPa ซึ่งผลจากงานวิจัยนี้ชี้ให้เห็นว่าการใช้สารตัวเติมแคลเซียมไดไฮโดรเจนฟอสเฟตช่วยให้เกิดเฟสของเหลวในกระบวนการเผาผนึกที่ส่งผลต่อโครงสร้างทางจุลภาคและสมบัติทางกลของชิ้นงานเซรามิกเซอร์โคเนียความหนาแน่นสูง


Nature-Inspired Material Strategies Towards Functional Devices, Sayantan Pradhan Jan 2021

Nature-Inspired Material Strategies Towards Functional Devices, Sayantan Pradhan

Theses and Dissertations

Naturally sourced, renewable biomaterials possess outstanding advantages for a multitude of biomedical applications owing to their biodegradability, biocompatibility, and excellent mechanical properties. Of interest in this dissertation are silk (protein) and chitin (polysaccharide) biopolymers for the fabrication of functional biodevices. One of the major challenges restricting these materials beyond their traditional usage as passive substrate materials is the ability to combine them with high-resolution fabrication techniques. Initial research work is directed towards the fabrication of micropatterned, flexible 2D substrates of silk fibroin and chitin using bench-top photolithographic techniques. Research is focused on imparting electrochemical properties to silk proteins using conducting …


Using Machine Learning To Interpret Dice Rolls, Hunter Wimsatt, Aarohi Panzade, Kaaustaaub Shankar, Warren Campbell Jan 2021

Using Machine Learning To Interpret Dice Rolls, Hunter Wimsatt, Aarohi Panzade, Kaaustaaub Shankar, Warren Campbell

SEAS Faculty Publications

Gamers use polyhedral dice that come with 4 sides (D4), 6 sides (D6), 8 sides (D8), 10 sides (D10), 12 sides (D12) and 20 sides (D20). All dice are unfair, some more than others. The goal of this project was to develop a machine learning and computer vision solution for the interpretation of dice rolls. When combined with an automated dice roller it would facilitate the study of dice unfairness. In the machine learning literature, Convolutional Neural Networks (CNNs) are the preferred method of computer classification of images. The CNN convolves images with different weights and biases through multiple layers …


Biomechanical Investigation Of Plant Vascular Tissue For Bio-Inspired Design And Flexible Composites, Mukesh Roy Jan 2021

Biomechanical Investigation Of Plant Vascular Tissue For Bio-Inspired Design And Flexible Composites, Mukesh Roy

Electronic Theses and Dissertations

Since the inception of evolution, nature has continuously optimized all the natural materials. These optimizations are so efficient that scientists and engineers have started taking inspiration from nature. Such inspiration-based solutions provide sustainable development of new materials with enhanced structural properties and functionalities (such as stiffness, stability, toughness, self-healing etc.). This variety of properties and functionalities is mainly due to the hierarchical organization of such components. Abstraction of the hidden cues of the hierarchical organization, principles and underlying structure-function relations are some of the critical approaches of bioinspired materials design. Inspiration from animals and plants has helped develop the design …


Development Of A High Strength Composite Material Using Large Scale 3d Printing Applications Using Waste Plastic And Steel, Naga Sri Madhavareddy Jan 2021

Development Of A High Strength Composite Material Using Large Scale 3d Printing Applications Using Waste Plastic And Steel, Naga Sri Madhavareddy

Electronic Theses and Dissertations

This project focuses on developing a high strength composite material for largescale 3D printing applications using recycled materials like High-Density Polyethylene (HDPE) and Steel 430. This material has applications for in-space manufacturing (the Moon or Mars) as well as large-scale manufacturing on earth. In addition to creating a strong useful material, materials that are easily recycled, but are often not recycled, are used. Recycling plastic and metal reduces pollution, saves resources, reduces waste going to landfills, and prevents the destruction of habitats from the polymerization of new plastic and similarly mining new ore. The percentage of HDPE generated from recycled …


Effect Of Composition And Print Orientation On Thermal Conductivity Of 3d Printed Composites, Cory Jacques Jan 2021

Effect Of Composition And Print Orientation On Thermal Conductivity Of 3d Printed Composites, Cory Jacques

Electronic Theses and Dissertations

Additive manufacturing (AM) technologies have become widely used for rapid prototyping and are beginning to be used for end-use applications. Fused Deposition Modeling (FDM) is a type of 3D printing where molten thermoplastic is extruded layer by layer to create parts. There is an increasing need for improvement and diversification of material properties to further extend the use of AM parts. AM parts have not been commonly used in heat transfer applications due to the limited availability of information on thermal conductivity of materials and the effects of printing orientation. A special apparatus was designed and built to experimentally test …


Printable Dielectric Elastomers Of High Electromechanical Properties Based On Sebs Ink Incorporated With Polyphenols Modified Dielectric Particles, Zhanxu Liu, Bangze Zhou, Chenchen Li, Yuhao Wang, Shipeng Wen, Yanfen Zhou, Liang Jiang, Fenglei Zhou, Tony Betts, Stephen Jerrams Jan 2021

Printable Dielectric Elastomers Of High Electromechanical Properties Based On Sebs Ink Incorporated With Polyphenols Modified Dielectric Particles, Zhanxu Liu, Bangze Zhou, Chenchen Li, Yuhao Wang, Shipeng Wen, Yanfen Zhou, Liang Jiang, Fenglei Zhou, Tony Betts, Stephen Jerrams

Articles

In this work, a recently developed 3D additive processing technology termed electrohydrodynamic (EHD) printing was employed to fabricate dielectric elastomer (DE) films by using styrene-ethylene-butylene-styrene (SEBS) inks with the addition of high dielectric titanium dioxide (TiO2) nanoparticles. In order to improve the dispersibility of TiO2 in the SEBS matrix, extracted walnut polyphenols were utilized for surface modification of TiO2 nanoparticles labelled wp-TiO2. The effect of the applied voltage on the ink jet morphology of the obtained SEBS based inks during EHD printing was analyzed. The prepared films had precision patterned shapes and their morphology was studied. It revealed that the …


Modeling Of Rare Earth Solvent Extraction Process For Flowsheet Design And Optimization, Vaibhav Kumar Srivastava Jan 2021

Modeling Of Rare Earth Solvent Extraction Process For Flowsheet Design And Optimization, Vaibhav Kumar Srivastava

Theses and Dissertations--Mining Engineering

The separation and purification of rare earth elements (REEs) into individual products has been a topic of significant interest for researchers and engineers for many decades. The prime reason for such sustained interest is due to REEs’ demand and application in modern technology, as well as the challenges associated with their separation and purification. The chemical similarity of rare earth group elements is responsible for difficult separability which makes purification of individual elements challenging. Despite associated complications, processes such as solvent extraction (SX) and ion-exchange have been successfully utilized in the separation and production of REEs on pilot and commercial …


Damage Assessment Of Glass Fiber Composites Using Dielectric Spectroscopy And Thermally Stimulated Depolarization Current, Bryan Durham, Gayathri Kola, Mohammadkian Mahroumi, Vamsee Vadlamudi, Rassel Raihan, Kenneth Reifsnider, Minhazur Rahman, Monjur Morshed Rabby, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian Jan 2021

Damage Assessment Of Glass Fiber Composites Using Dielectric Spectroscopy And Thermally Stimulated Depolarization Current, Bryan Durham, Gayathri Kola, Mohammadkian Mahroumi, Vamsee Vadlamudi, Rassel Raihan, Kenneth Reifsnider, Minhazur Rahman, Monjur Morshed Rabby, Partha Pratim Das, Muthu Ram Prabhu Elenchezhian

Institute of Predictive Performance Methodologies (IPPM-UTARI)-Archive

A composite is generally defined as a material composed of two or more separate sub-materials that complement each other's characteristics when combined. Composites are widely used in several major industries due to their low density, high strength, and relatively predictable chemical and electrical properties. One of the significant challenges of integrating composites into more diverse fields is the ability to accurately and consistently test for damages. Due to the myriad number of microscopic structures available in composite materials, a single-use testing system is a large contributor to current research. One approach to the non-destructive testing of composites lies in exploiting …


Deformation Manifold Learning Model For Multi Walled Carbon Nanotubes, Shashank S. Pathrudkar Jan 2021

Deformation Manifold Learning Model For Multi Walled Carbon Nanotubes, Shashank S. Pathrudkar

Dissertations, Master's Theses and Master's Reports

Two-Dimensional (2D) materials are being studied widely by researchers due to their superior material properties over the bulk materials. Since the isolation of graphene in 2004, graphene has gained popularity amongst the 2D materials community. Graphene when rolled into sheets form Carbon Nanotubes (CNTs) which possess excellent mechanical and electrical properties. Concentric stacks of CNTs yield Multi-walled Carbon Nanotubes (MWCNTs) which are superior to CNTs in certain aspects. It has been well established that the deformation of CNTs and MWCNTs change their mechanical and electrical properties significantly. This has opened doors for CNTs into numerous applications and also piqued the …


Novel Design And Facile Synthesis Of Functional Nanostructures For Energy And Environmental Application, Zhuojun Wang Jan 2021

Novel Design And Facile Synthesis Of Functional Nanostructures For Energy And Environmental Application, Zhuojun Wang

Wayne State University Theses

Environmental pollution and energy crisis are two of the major obstacles in the development of a more sustainable society. It is an interesting but technically challenging task to design novel methods for the facile and scalable synthesis of multifunctional materials for applications in both energy storage and environmental remediation. In this thesis, I tried to design and synthesize novel nanostructured materials for energy and environmental applications, achieved highly promising results. I developed a facile electrochemical approach to synthesize the zinc oxide with the zinc element for photocatalytic reactions. It demonstrated dramatically improved performances in degradation of organic pollutant in water, …


Uv-Ozone Oxide Treatments For High-Efficiency Silicon Photovoltaic Devices, Munan Gao Jan 2021

Uv-Ozone Oxide Treatments For High-Efficiency Silicon Photovoltaic Devices, Munan Gao

Electronic Theses and Dissertations, 2020-2023

Fabrication of solar cells with higher efficiency, simpler processes and lower cost is largely perceived as the ultimate goal for photovoltaic research. To reach such a goal each step needs to be refined and optimized. In this dissertation, a UV-ozone treatment is proposed as a simple and versatile process that can be applied to multiple fabrication steps for improvement. The UV-ozone cleaning method provides comparable surface cleaning quality to more expensive and hazardous industrial standard RCA clean with less chemical used. A good passivation quality was achieved on both n-type and p-type silicon wafer by a silicon oxide/aluminum oxide passivation …


Investigation Of Cation Exchange Behaviors Of FaXMa1-XPbl3 Films Using Dynamic Spin Coating, Hyang Mi Yu, Byeong Geun Jeong, Dae Young Park, Seong Chu Lim, Gon Namkoong, Mun Seok Jeong Jan 2021

Investigation Of Cation Exchange Behaviors Of FaXMa1-XPbl3 Films Using Dynamic Spin Coating, Hyang Mi Yu, Byeong Geun Jeong, Dae Young Park, Seong Chu Lim, Gon Namkoong, Mun Seok Jeong

Applied Research Center Publications

In this study, we fabricated and characterized uniform multi-cation perovskite FAxMA1−xPbI3 films. We used the dynamic spin-coating method to control the cation ratio of the film by gradually increasing the FA+, which replaced the MA+ in the films. When the FA+ concentration was lower than xFA ~0.415 in the films, the stability of the multi-cation perovskite improved. Above this concentration, the film exhibited δ-phase FAPbI3 in the FAxMA1−xPbI3 films. The formation of δ-phase FAPbI3 disturbed the homogeneity of the photoluminescence spatial distribution and suppressed the absorption spectral bandwidth …


Applied Machine Learning In Extrusion-Based Bioprinting, Shuyu Tian Jan 2021

Applied Machine Learning In Extrusion-Based Bioprinting, Shuyu Tian

Theses and Dissertations

Optimization of extrusion-based bioprinting (EBB) parameters have been systematically conducted through experimentation. However, the process is time and resource-intensive and not easily translatable across different laboratories. A machine learning (ML) approach to EBB parameter optimization can accelerate this process for laboratories across the field through training using data collected from published literature. In this work, regression-based and classification-based ML models were investigated for their abilities to predict printing outcomes of cell viability and filament diameter for cell-containing alginate and gelatin composite hydrogels. Regression-based models were investigated for their ability to predict suitable extrusion pressure given desired cell viability when keeping …


Tailoring Texture, Microstructure, And Shape Memory Behavior Of Niti Alloys Fabricated By L-Pbf-Am, Sayed Ehsan Saghaian N.E. Jan 2021

Tailoring Texture, Microstructure, And Shape Memory Behavior Of Niti Alloys Fabricated By L-Pbf-Am, Sayed Ehsan Saghaian N.E.

Theses and Dissertations--Mechanical and Aerospace Engineering

Laser Powder Bed Fusion (L-PBF) is one of the most promising Additive Manufacturing (AM) methods to fabricate near net-shape metallic materials for a wide range of applications such as patient-specific medical devices, functionally graded materials, and complex structures. NiTi shape memory alloys (SMAs) are of great interest due to a combination of unique features, such as superelasticity, shape memory effect, high ductility, work output, corrosion resistance, and biocompatibility that could be employed in many applications in automotive, aerospace, and biomedical industries. Due to the difficulties with traditional machining and forming of NiTi components, the ability to fabricate complex parts, tailor …


Viscoelasticity Of Ptfe-Based Face Seals, Bo Tan Jan 2021

Viscoelasticity Of Ptfe-Based Face Seals, Bo Tan

Theses and Dissertations--Mechanical and Aerospace Engineering

PTFE-based materials are widely used in areas of tribology, particularly in seal and bearing applications because of their outstanding self-lubricating properties. Often in dynamic seal applications there is a need for ultra-low mechanical friction loss between the sealing surfaces. Due to its extremely low friction coefficient, there is interest in employing Polytetrafluoroethylene (PTFE) materials in such applications. One challenging aspect of employing PTFE is that these materials are viscoelastic and plastic. This dissertation concentrates on the modeling of viscoelastic material response when used as mechanical face seals with a focus on PTFE-based materials. First, the viscoelastic characteristics are measured through …


Development Of An Injectable Methylcellulose Hydrogel System For Nucleus Pulposus Repair And Regeneration, Nada A. Haq-Siddiqi Jan 2021

Development Of An Injectable Methylcellulose Hydrogel System For Nucleus Pulposus Repair And Regeneration, Nada A. Haq-Siddiqi

Dissertations and Theses

Low back pain is the most common cause of disability in the world and is often caused by degeneration or injury of the intervertebral disc (IVD). The IVD is a complex, fibrocartilaginous tissue that allows for the wide range of spinal mobility. Disc degeneration is a progressive condition believed to begin in the central, gelatinous nucleus pulposus (NP) region of the tissue, for which there are few preventative therapies. Current therapeutic strategies include pain management and exercise, or surgical intervention such as spinal fusion, none of which address the underlying cause of degeneration. With an increasingly aging population, the socioeconomic …


Microstructure Evolution And Mechanical Property Response Of Tc11 Titanium Alloy Under Electroshock Treatment, Chang Liu, Lechun Xie, Dongsheng Qian, Lin Hua, Liqiang Wang, Lai-Chang Zhang Jan 2021

Microstructure Evolution And Mechanical Property Response Of Tc11 Titanium Alloy Under Electroshock Treatment, Chang Liu, Lechun Xie, Dongsheng Qian, Lin Hua, Liqiang Wang, Lai-Chang Zhang

Research outputs 2014 to 2021

© 2020 The Authors This work investigated the effects of electroshock treatment (EST) on the microstructure variation and mechanical properties of TC11 alloy. The average hardness of the specimens decreased from 358 HV to 328 HV after EST of 0.04 s, then increased to 396 HV after EST of 0.06 s. After EST, the yield strength of specimen declined from 959 MPa to 797 MPa after EST of 0.04 s, and then increased to 1265 MPa after EST of 0.06 s, but the fracture strain decreased continuously. The variation in mechanical properties was closely related to the phase transition from …


Synthesis And Catalytic Properties Of Metal-Organic Frameworks Mimicking Carbonic Anhydrase, Longji Li Jan 2021

Synthesis And Catalytic Properties Of Metal-Organic Frameworks Mimicking Carbonic Anhydrase, Longji Li

Mahurin Honors College Capstone Experience/Thesis Projects

The natural enzyme carbonic anhydrase has gained attention in recent years for its ability to catalyze the interconversion of aqueous carbon dioxide (CO2) and bicarbonate. However, it lacks the efficiency to qualify practical usage on a large scale due to its inherent deficiency and fragile nature. On the other hand, its active center can be used as an ideal model for the design of novel catalytic materials targeting carbon dioxide capture and sequestration. This study focused on the synthesis of a zinc-based metal-organic framework (Zn-MOF-1) mimicking the carbonic anhydrase using the solvothermal method. Important properties such as catalytic …


Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu Jan 2021

Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu

College of Graduate Studies: Theses & Dissertations

In recent years, lightweight structures have become mature and adopted in various applications. The importance of quality assurance cannot be overemphasized hence extensive research has been conducted to assess the quality of lightweight structures. This study investigates a novel process that exploits motion magnification to investigate the damage characteristics of lightweight mission-critical parts. The goal is to assure the structural integrity of 3D printed structures and composite structures by determining the inherent defects present in the part by exploiting their vibration characteristics. The minuscule vibration of the structure was recorded with the aid of a high-speed digital camera, and the …


Interface Characterization In Tungsten Fiber/Zr-Based Bulk Metallic Glass Matrix Composite, Mohammad Ammar Mofid, Mostafa Jafarzadegan Jan 2021

Interface Characterization In Tungsten Fiber/Zr-Based Bulk Metallic Glass Matrix Composite, Mohammad Ammar Mofid, Mostafa Jafarzadegan

Journal of Metals, Materials and Minerals

In this research, Zr55Cu30Al10Ni5 bulk metallic glass (BMG) alloy is used as the base material to form tungsten fiber reinforced BMG composites. The composites are synthetized using melt infiltration casting method and their microstructure and compressive properties are investigated. Two different infiltration times of 10 min and 15 min are used to produce the composites. The microstructural evaluation of the interface between tungsten fiber and BMG matrix reveals that a narrow reaction band emerges between the tungsten wires and BMG alloy. Some portions of this layer are broken into the fine Zr/W-rich particles …


On The Mechanical Properties Of Al/Cu-Grid/Al Intermetallic Composite, Hamza Essoussi, Said Ettaqi Jan 2021

On The Mechanical Properties Of Al/Cu-Grid/Al Intermetallic Composite, Hamza Essoussi, Said Ettaqi

Journal of Metals, Materials and Minerals

The present paper deals with the experimental investigation of new process combining static compression with high temperature as a simple way to prepare new Al/Cu-grid/Al metallic composite (MC) that consists of Aluminum matrix and Copper grid acting as ductile reinforcement stacked between the Al sheets. At the stage of composite fabrication, two different thermal cycles were tested to highlight the effect of processing temperature on the layers’ adherence and the mechanical properties of the prepared composites. Consequently, the microstructural and mechanical results revealed that the compression at 630℃ for 30 min, then furnace cooled to 450℃ followed by air cooling …


Thermal Behavior Of Solid Acids In The Rb3h(So4)2-Rbhso4 System Under Ambient Atmosphere, Chatr Panithipongwut Kowalski, Permpoon Chaijaroen, Farook Kaewniyom Jan 2021

Thermal Behavior Of Solid Acids In The Rb3h(So4)2-Rbhso4 System Under Ambient Atmosphere, Chatr Panithipongwut Kowalski, Permpoon Chaijaroen, Farook Kaewniyom

Journal of Metals, Materials and Minerals

The thermal behavior of solid acids in the Rb3H(SO4)2-RbHSO4 system under ambient atmosphere has been studied in comparison to the previously reported high-temperature behavior of the same system under humidified atmosphere. The findings showed that, under this level of humidity, the transition of RbHSO4, the transition of Rb5H3(SO4)4, and the disproportionation of Rb3H(SO4)2, occurred at the same temperatures as those under humidified atmosphere. However, the results from differential scanning calorimetry did not reveal the reaction temperature between Rb3H(SO4)2 and RbHSO4 due to the slow process. The dehydration temperatures of Rb5H3(SO4)4 were surprisingly similar between the systems under low and high …


Synthesis Of A Two-Part Geopolymer From Red Mud And Silica Fume, Arup Kumar Mandal Jan 2021

Synthesis Of A Two-Part Geopolymer From Red Mud And Silica Fume, Arup Kumar Mandal

Journal of Metals, Materials and Minerals

In this present study, the development of a two-part geopolymer from waste red mud (RM) and silica fume (SF) by alkali activator is examined. The influence of silica fume addition, alkali concentration, curing duration are studied. The compressive strength of geopolymers has been achieved 0.8 MPa to 8 MPa with varying different compositions and synthesis parameters. The optimum RM/SF ratio is 60/40, the optimum solid/solution ratio is 1.8 gmL-1 or 2 gmL-1, and the optimum Na2SiO3/NaOH ratio is 0.5 day for 28 days curing time. The incorporation of iron in the geopolymer matrix contributes to geopolymerization. The study suggests that …


Debinding Behaviour And Sintering Temperature-Dependent Features Of Coloured Zirconia Fabricated By Ceramic Injection Moulding, Wantanee Buggakupta, Thanakorn Wasanapiarnpong, Nutthita Chuankrerkkul Jan 2021

Debinding Behaviour And Sintering Temperature-Dependent Features Of Coloured Zirconia Fabricated By Ceramic Injection Moulding, Wantanee Buggakupta, Thanakorn Wasanapiarnpong, Nutthita Chuankrerkkul

Journal of Metals, Materials and Minerals

Zirconia (ZrO2) is one of ceramic materials that has very good mechanical and chemical properties suitable for biomedical applications as well as other industrial applications. ZrO2 ceramics, in fact, has been used in orthodontic dentistry. Nowadays, ZrO2 has been played its role in decorative and jewelry purposes, such as watchcases and artificial stones. Ceramic injection moulding (CIM), a near-net shape manufacturing process that can produce small, complex-shaped components and is suitable for large volume production, is one of the best powder fabrication methods. In this work, CIM was carried out in order to form the coloured-ZrO2 specimens. Binders used in …


Graphene Enhanced Linear Low-Density Polyethylene Nanocomposites By Premixing And Melt Compounding, Wan Nazri Wan Busu, Ruey Shan Chen, Muhammad Jefri Mohd Yusof, Sahrim Ahmad Jan 2021

Graphene Enhanced Linear Low-Density Polyethylene Nanocomposites By Premixing And Melt Compounding, Wan Nazri Wan Busu, Ruey Shan Chen, Muhammad Jefri Mohd Yusof, Sahrim Ahmad

Journal of Metals, Materials and Minerals

In this study, linear low-density polyethylene/graphene nanoplatelets (LLDPE/GNPs) nanocomposites were prepared from conventional melt-mixing method and our new approach; two-step premix mixing technique. Indirect mixing technique (IDT) was employed to fabricate a premix of LLDPE/ GNPs in the ratio of 80:20 wt%. The effects of GNPs loadings and the processing method of nanocomposites on the mechanical strength, decomposition temperature, crystallinity, electrical impedance and morphology were investigated. Irrespective of processing methods, the prepared nanocomposites exhibited crystalline structure due to the presence of GNPs whilst the degradation temperature was recorded to be increased with GNPs loadings that signified improved thermal stability. The …


Enhancing Stability And Antioxidant Efficacy Of Fisetin By Encapsulating As Β-Cyclodextrin Inclusion Complex With Porous Polylactic Acid Film From Breath Figure, Charasphat Preuksarattanawut, Warinyupa Mangmee, Munchumas Prousoontorn, Ekasit Nisarattanaporn, Krisana Siraleartmukul Jan 2021

Enhancing Stability And Antioxidant Efficacy Of Fisetin By Encapsulating As Β-Cyclodextrin Inclusion Complex With Porous Polylactic Acid Film From Breath Figure, Charasphat Preuksarattanawut, Warinyupa Mangmee, Munchumas Prousoontorn, Ekasit Nisarattanaporn, Krisana Siraleartmukul

Journal of Metals, Materials and Minerals

This research aims to investigate the scope of fisetin (FIT)/β-cyclodextrin (β-CD) inclusion complexes with the ratios of 1:2 and 2:1 mole by means of freeze-drying, kneading and physical mixing methods (controlled process). Moreover, the complex compounds are analyzed by Fourier-Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). The results show that the most suitable preparation method of fisetin (FIT)/β-CD complex is the freeze-drying method with the fisetin (FIT) to β-CD ratio at 1:2. The emission of FIT/β-CD was investigated and it is found that the emission rate of freeze-dried FIT/β-CD in 1:2 ratio by freeze-drying method is lower than …


Using Shrimp Shells As Based Catalysts For Fame Production From Palm Oil Feedstock, Assadaporn Poonanan, Anupat Prukpaiboon, Paul Egwuonw Dim, Mutsee Termtanun Jan 2021

Using Shrimp Shells As Based Catalysts For Fame Production From Palm Oil Feedstock, Assadaporn Poonanan, Anupat Prukpaiboon, Paul Egwuonw Dim, Mutsee Termtanun

Journal of Metals, Materials and Minerals

In this study, waste shrimp shells from industry were used as a heterogeneous bio-based catalyst for trans-esterification reaction of fresh palm oil. CaO was prepared from shrimp shells calcination. Surface area, phase composition, and basicity of the calcined shrimp shell catalysts were studied using N2 adsorption (BET), X-ray diffraction (XRD), and CO2 temperature-programmed-desorption (CO2-TPD), respectively. The influence of shrimp shells calcination temperature and operation condition, methanol to palm oil ratio on trans-esterification reaction, were investigated. Five hours trans-esterification was carried out at 65℃ using different shrimp shell at four different calcination temperature: 700, 750, 800 and 850℃ with 9:1 methanol …


Preparation Of Transparent Alumina Thin Films Deposited By Rf Magnetron Sputtering, Busarin Noikaew Noikaew, Laksana Wangmooklang, Saisamorn Niyomsoan, Siriporn Larpkiattaworn Jan 2021

Preparation Of Transparent Alumina Thin Films Deposited By Rf Magnetron Sputtering, Busarin Noikaew Noikaew, Laksana Wangmooklang, Saisamorn Niyomsoan, Siriporn Larpkiattaworn

Journal of Metals, Materials and Minerals

Alumina (Al2O3) thin films were prepared by RF magnetron sputtering technique using Al2O3 ceramic target. Effects of sputtering powers and oxygen gas mixtures were investigated and the optimized coating condition was applied on semi-precious gemstones. RF sputtering powers were varied to optimize the transparency of the films. Besides, the oxygen gas mixtures were also studied at the optimized sputtering power with a constant sputtering pressure. Optical and physical properties of the thin films were investigated using UV-Vis Spectrophotometer, FESEM, XRF, GIXRD, XRR including a microscratch tester. The Al2O3 films were highly transparent in the visible region in form of an …