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Full-Text Articles in Engineering

The Study On Un-Doped/Boron Doped/Un-Doped Triple Seg In Vertical Nand Flash Memory, Woong Lee, Chaeho Kim, Joonsuk Lee, Sehun Park, Yonghan Roh Jan 2021

The Study On Un-Doped/Boron Doped/Un-Doped Triple Seg In Vertical Nand Flash Memory, Woong Lee, Chaeho Kim, Joonsuk Lee, Sehun Park, Yonghan Roh

Journal of Metals, Materials and Minerals

Selective epitaxial growth (SEG) plays a critical role in vertical NAND flash memory because it serves as a ground select line (GSL) transistor, which is used to control the cell current in the vertical channel. In this study, different channel hole sizes between the adjacent hole and away hole from the common source line (CSL) were detected after vertical channel etch (VCE). This discrepancy severely impacts the boron concentration of SEG applied through ex-situ boron implantation, and results in large GSL Vth variations. Novel in-situ boron-doping of triple-layered un-doped/boron doped/un-doped SEG was developed to solve the high variation of the …


Microwave-Assisted Ecofriendly Silver Nanoparticle Synthesis By Varieties Of Chrysanthemum Morifolium Ramat: Assessing Their Antioxidant, Photocatalytic And Antibacterial Activities, Mathivathani Kandiah, Laknee Nawamali De Silva Jan 2021

Microwave-Assisted Ecofriendly Silver Nanoparticle Synthesis By Varieties Of Chrysanthemum Morifolium Ramat: Assessing Their Antioxidant, Photocatalytic And Antibacterial Activities, Mathivathani Kandiah, Laknee Nawamali De Silva

Journal of Metals, Materials and Minerals

Based on recent developments in the field of Nanobiotechnology, this study is aimed at the assessment of antioxidant, photocatalytic and antibacterial activities of silver nanoparticles (AgNPs) synthesized using Chrysanthemum morifolium Ramat varieties (brown, yellow, purple, pink, salmon pink and white), where five varieties produced AgNPs except white. Antioxidant assays such as total flavonoid content, total phenolic content and total antioxidant capacity and free radical scavenging assays such as ferric reducing antioxidant power and DPPH radical scavenging assays were performed. Photocatalytic activity was assessed by the degradation of the model dye methylene blue. Anti-bacterial activity was determined on Staphylococcus aureus and …


Improvement Of The Superconducting Properties Of Carbon Addition On Bi1.6pb0.4sr2 Ca2cu3o10+Δ Prepared Through The Two-Step Sintering Process, Dini Rizqi Dwikunti Siregar, Sigit Dwi Yudanto, Septian Adi Chandra, Eka Feby Ronauli Lubis, Syahrul Humaidi, Nono Darsono Jan 2021

Improvement Of The Superconducting Properties Of Carbon Addition On Bi1.6pb0.4sr2 Ca2cu3o10+Δ Prepared Through The Two-Step Sintering Process, Dini Rizqi Dwikunti Siregar, Sigit Dwi Yudanto, Septian Adi Chandra, Eka Feby Ronauli Lubis, Syahrul Humaidi, Nono Darsono

Journal of Metals, Materials and Minerals

The effects of the addition of carbon nanoparticles and nanotubes on the Bi1.6Pb0.4Sr2Ca2Cu3O10+δ (BPSCCO) have been reported. BPSCCO samples were synthesized using the sol-gel method. BPSCCO with nominal composition was sintered at 840°C for 30 h, then grounded and added an amount of carbon. Pure and carbon added BPSCCO were sintered at 840°C for 30 hours. Resistivity measurements were carried out to determine the superconducting properties of the samples. We found that the addition of carbon nanoparticles and nanotubes increased the critical zero temperature (Tc-zero) of BPSCCO from 94.67 K to 97.8 K and 102.03 K for the pure BPSCCO, …


Stress Softening Characteristics Of Thin Monoholar Rubber Flat Slab, Kulyuth Boonseng, Chatchai Waiyapattanakorn, Prayoon Surin Jan 2021

Stress Softening Characteristics Of Thin Monoholar Rubber Flat Slab, Kulyuth Boonseng, Chatchai Waiyapattanakorn, Prayoon Surin

Journal of Metals, Materials and Minerals

Thin monoholar rubber flat slab gives rise to unconventional mechanical properties under tension loading not found in thin solid rubber flat slab. However there has been no proper report on its stress softening characteristics. Stress softening is an important phenomenon occurring in all elastomeric materials under cyclic tension loading. Parameters pertinent to stress softening investigated in this research are stress-strain characteristics, permanent set strain and hysteresis loss energy of the thin monoholar rubber flat slab in comparison with the thin solid rubber fat slab when undergoing 7 cycles of stretching. Noticeable differences of stress-strain hysteresis loops diminution of the thin …


Photoelectrochemical Cathodic Protection Of Amorphous Zinc Oxide Coating On Hot Rolled Steel Ss400 In A 3 Wt% Nacl Solution And A Na2s-Naoh Solution, Phatchara Wipataphan, Worapot Sripianem, Naw Blessing Oo, Thanate Na Wichean, Boossayamas Dachbumroong, Oratai Jongprateep, Gasidit Panomsuwan, Naray Pewnim, Ratchatee Techapiesancharoenkij Jan 2021

Photoelectrochemical Cathodic Protection Of Amorphous Zinc Oxide Coating On Hot Rolled Steel Ss400 In A 3 Wt% Nacl Solution And A Na2s-Naoh Solution, Phatchara Wipataphan, Worapot Sripianem, Naw Blessing Oo, Thanate Na Wichean, Boossayamas Dachbumroong, Oratai Jongprateep, Gasidit Panomsuwan, Naray Pewnim, Ratchatee Techapiesancharoenkij

Journal of Metals, Materials and Minerals

The photoelectrochemical cathodic protection of amorphous ZnO thin-film coating on hot rolled steel SS400, in the 3 wt% NaCl environment, was investigated. The ZnO thin film was coated on a SS400 substrate at 200℃ using the spray pyrolysis technique. The x-ray diffractometry analysis confirmed the amorphous ZnO coatings. Two different types of the electrochemical cells were used: a single-cell and a double-cell system. Two different types of the photoelectrolytic solutions were compared: (i) 0.1 M Na2S + 0.2 M NaOH and (ii) 3 wt% NaCl solution. The ZnO-coated SS400 samples were subjected to potentiostatic polarization testing under dark and UV …


Influence Of Graphite Feedstock On The Characteristics Of Silver-Decorated Graphene Oxide And Antimicrobial Property, Ebrahim Mahmoudi, Wei Lun Ang, Gasidit Panomsuwan, Oratai Jongprateep, Abdul Wahab Mohammad, Law Yong Ng, Muneer M. Ba-Abbad Jan 2021

Influence Of Graphite Feedstock On The Characteristics Of Silver-Decorated Graphene Oxide And Antimicrobial Property, Ebrahim Mahmoudi, Wei Lun Ang, Gasidit Panomsuwan, Oratai Jongprateep, Abdul Wahab Mohammad, Law Yong Ng, Muneer M. Ba-Abbad

Journal of Metals, Materials and Minerals

Graphite from different sources has significant influence on the properties of graphene oxide (GO) and reactivity of GO towards further modification with other nanoparticles. However, such effect has not yet been properly explored. This study aims to investigate the characteristics and antimicrobial property of GO decorated with silver nanoparticles (known as Ag-GO composite) where the GO is synthesized via modified Hummer’s method from various graphite feedstock, namely natural graphite flake (NGF), natural graphite powder (NGP), and synthetic graphite powder (SGP). The Ag-GO nanocomposite was then synthesized using chemical reduction methods. Antimicrobial properties of the Ag-GO were tested using the standard …


Preparation Of A Mixed Al/Sc Nano-Oxide Derived From The Bauxite Residue (Red Mud) Via The Sulfuric Acid Roasting–Leaching–Precipitation Process, Razieh Habibpour, Eslam Kashi, Mehdi Janfada Jan 2021

Preparation Of A Mixed Al/Sc Nano-Oxide Derived From The Bauxite Residue (Red Mud) Via The Sulfuric Acid Roasting–Leaching–Precipitation Process, Razieh Habibpour, Eslam Kashi, Mehdi Janfada

Journal of Metals, Materials and Minerals

In this study, three methods were used and compared for the selectable extraction of aluminum/ scandium with the least amount of iron in red mud (RM) samples from the Iran alumina plant in Jajarm as follows: 1) RM direct acid leaching with H2SO4, 2) RM washing with hydrochloric acid and oxalic acid before leaching with H2SO4, and 3) RM sulfuric acid roasting-leaching-precipitation.  The aim was to extract the highest amount of scandium while preventing the leaching of other metals, especially iron. Due to any discriminative features, the selective separation of Al/Sc with …


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 …


Spatial-Temporal Patterns Of Modis Active Fire/Hotspots In Chiang Rai, Upper Northern Thailand And The Greater Mekong Subregion Countries During 2003-2015, Chidsanuphong Chart-Asa Jan 2021

Spatial-Temporal Patterns Of Modis Active Fire/Hotspots In Chiang Rai, Upper Northern Thailand And The Greater Mekong Subregion Countries During 2003-2015, Chidsanuphong Chart-Asa

Applied Environmental Research

For the past decade, smoke-haze pollution from forest fires and open burning has been a yearly recurring problem over Chiang Rai and other provinces in Upper Northern Thailand, along with other countries in the Greater Mekong Sub-region. Remote-sensing active fire/ hotspot data are currently used for monitoring the forest fires and open burning in the sub-region. This study aimed to extend the current monitoring work by performing spatial and temporal analysis to examine the patterns, either globally or locally, of MODIS active fires/hotspots during the critical smoke-haze pollution periods from January to April in 2003-2015. Fire radiative power was used …


Comparison Of Direct-Reading And Gravimetric Methods Of Particle Measurement In A Science Building, Silpakorn University, Aungsiri Tipayarom, Prayad Sangngam, Siraphop Pinitkarn Jan 2021

Comparison Of Direct-Reading And Gravimetric Methods Of Particle Measurement In A Science Building, Silpakorn University, Aungsiri Tipayarom, Prayad Sangngam, Siraphop Pinitkarn

Applied Environmental Research

This study aimed to develop relationships between particulate matter (PM) concentrations obtained from a direct-reading instrument to those from a gravimetric method. TSI DustTrak II Aerosol Monitors (Model 8530), a direct-reading instrument for PM10 and PM2.5 measurement, together with personal air pumps connected to a Sensidyne cyclone and a SKC Personal Environmental Monitor (PEM) for gravimetric PM10 and PM2.5 measurements respectively were deployed in the Faculty of Science building, Silpakorn University, Nakhon Pathom, Thailand. Comparison of the results from each instrument indicated that PM10 and PM2.5 concentrations obtained from the TSI DustTrak were higher. The linear relationship from ordinary least …


Ozone Formation Potential Of Ambient Volatile Organic Compounds At Roadside In Bangkok, Thailand, Narita Fakkaew, Surat Bualert, Thunyapat Thongyen, Thitima Rungratanaubon Jan 2021

Ozone Formation Potential Of Ambient Volatile Organic Compounds At Roadside In Bangkok, Thailand, Narita Fakkaew, Surat Bualert, Thunyapat Thongyen, Thitima Rungratanaubon

Applied Environmental Research

Volatile organic compounds (VOCs) play an important role in atmospheric chemistry due to their high reactivity—reacting photochemically with oxides of nitrogen (NOx) in the presence of solar radiation forming tropospheric ozone (O3). Each VOC species have different effects on ozone formation according to the rates and pathways of their reactions. The objective of this study aims to examine ozone formation from the estimation of ozone formation potential (OFP). The observation of 29 VOCs species was carried out in the urban area near the roads of Bangkok, Thailand. Measurements were carried out during the dry season, from 16th February to 15th …


Fire Drivers Affecting Forest Fire Occurrences In The Tropical Mixed Broad-Leaved Forests Of Nepal, Krishna Bahadur Bhujel, Rejina Maskey Byanju, Ambika P. Gautam, Ramesh Prasad Sapkota, Udhab Raj Khadka Jan 2021

Fire Drivers Affecting Forest Fire Occurrences In The Tropical Mixed Broad-Leaved Forests Of Nepal, Krishna Bahadur Bhujel, Rejina Maskey Byanju, Ambika P. Gautam, Ramesh Prasad Sapkota, Udhab Raj Khadka

Applied Environmental Research

Forest fires triggered by various natural and anthropogenic drivers are increasing and threatening forest ecosystems across the globe. In Nepal, the high value Tropical Mixed Broad-leaved Forests are prone to fire caused by both natural and anthropogenic drivers. Thus, understanding fire drivers and their effect is important for the sustainable forest fire management. However, the preceding studies on forest specific fire drivers and their effect are limited. This research has identified the fire drivers and assessed their effect to fire occurrences in the Tropical Mixed Broad-leaved Forests of Nawalparasi District, Nepal. Fire drivers were identified and prioritized by participatory approaches. …


Life Cycle Assessment Of Ethiopian Cement Manufacturing: A Potential Improvement On The Use Of Fossil Fuel In Mugher Cement Factory, Lemma Beressa, Battula Vijaya Saradhi Jan 2021

Life Cycle Assessment Of Ethiopian Cement Manufacturing: A Potential Improvement On The Use Of Fossil Fuel In Mugher Cement Factory, Lemma Beressa, Battula Vijaya Saradhi

Applied Environmental Research

The use of imported fuel in the Ethiopian cement industry increased the cost of production and the environmental burden, necessitating intervention. The greenhouse gas (GHG) emission, energy usage intensity, and resource exploitation of Ethiopian cement production were evaluated using the life cycle impact assessment (LCA) tool, aiming to recommend improvements. The LCA study used cumulative energy demand (CED) and Intergovernmental Panel on Climate Change (IPCC) 2006 life cycle impact assessment (LCIA) methods. For the case study of Mugher cement factory (MCF), the results on energy use intensities showed 3.74, 3.67, and 2.64 GJ/ton of clinker, Ordinary Portland cement (OPC), Pozzolana …


Critical Factors And Their Correlation Affecting Green Industry Performance: Evidences From Small And Medium Enterprises, Phurita Noranarttakun, Chanathip Pharino Jan 2021

Critical Factors And Their Correlation Affecting Green Industry Performance: Evidences From Small And Medium Enterprises, Phurita Noranarttakun, Chanathip Pharino

Applied Environmental Research

Large companies have achieved excellent progress toward green production while small and medium enterprises (SMEs) showed limited progress. This research aims to investigate key factors affect different stages of enhancing green industry implementation particularly in SMEs. This study conducted a systematic analysis to offer recommendations to unlock the inhibitors of the green industry. The electronic products and electrical equipment manufacturing industry in Thailand was chosen as a case study. Questionnaire is the main approach to collect primary data from SMEs. The structural equation model is developed to examine correlation and the degree of influencing factors. The model indicated that the …


Why Should Different City Characteristics Customize The Rate Of Pollution Charge? Evidence Of Factors Affecting Willingness-To-Pay For Wastewater Management In Thailand, Kwanmanas Meethavorn, Chanathip Pharino Jan 2021

Why Should Different City Characteristics Customize The Rate Of Pollution Charge? Evidence Of Factors Affecting Willingness-To-Pay For Wastewater Management In Thailand, Kwanmanas Meethavorn, Chanathip Pharino

Applied Environmental Research

A challenge for wastewater management is enhancing the efficiency of resource allocation. Polluter Pays Principle is a wastewater charge collection approach that could help support the financial burden faced by many countries. Tailor-made policy implementation based on city characteristics is critical to the success of implementing a national policy to fit well in different local contexts. This study examined gaps for improving municipal wastewater management systems in Thailand through in-depth interviews and a questionnaire survey to identify the factors influencing households’ perception and willingness to pay in three different cities. A contingent variation method technique was used to evaluate the …


Centuries Of Heat Waves Over India During 20th And 21st Century, Naveena Neelam, Gubbala C. Satyanerayana, Kotla S. Rao, Nandivada Umakantha, Dharma Raju Jan 2021

Centuries Of Heat Waves Over India During 20th And 21st Century, Naveena Neelam, Gubbala C. Satyanerayana, Kotla S. Rao, Nandivada Umakantha, Dharma Raju

Applied Environmental Research

An assessment of temperature extremes is made for the Indian subcontinent to identify the changes since 1951 to 2015, and for the future climate periods till 2100 for all the 21 CMIP5 (Coupled Model intercomparision Project phase 5) models and the representative concentration pathways RCP4.5 and RCP8.5 were examined for the period from 1 March to 31 May to characterize the heat waves in future climates and mean maximum and mean minimum bias were evaluated for the Indian subcontinent. Later two highest recorded temperature regions were chosen Northwest & Central India (NW&CIN) and only central India (CIN) box and the …


Source Contribution Of 1,3 Butadiene In The Vicinity Of Petrochemical Industrial Area, Nuttakit Sukjit, Sarawut Thepanondh, Suphaphat Kwonpongsagoon, Wanida ๋Jinsart, Lalidaporn Punya, Pattaranan Hanma Jan 2021

Source Contribution Of 1,3 Butadiene In The Vicinity Of Petrochemical Industrial Area, Nuttakit Sukjit, Sarawut Thepanondh, Suphaphat Kwonpongsagoon, Wanida ๋Jinsart, Lalidaporn Punya, Pattaranan Hanma

Applied Environmental Research

Emissions and ambient concentrations of 1,3 butadiene released from the synthetic rubber industries in the largest petroleum and petrochemical complex in Thailand were evaluated in this study. The industrial emissions in this analysis were those emitted from process fugitive, combustion stack, flare, and wastewater treatment facility. It was found that wastewater treatment units were the largest emission source among other potential sources. The contribution of emission from wastewater treatment plants were about 92% of total 1,3 butadiene emission. The extent and magnitude of 1,3 butadiene in ambient air were further evaluated through the simulation of AERMOD dispersion model using these …


Land Cover Classification Based On Uav Photogrammetry And Deep Learning For Supporting Mine Reclamation: A Case Study Of Mae Moh Mine In Lampang Province, Thailand, Tejendra K. Yadav, Polpreecha Chidburee, Nattapon Mahavik Jan 2021

Land Cover Classification Based On Uav Photogrammetry And Deep Learning For Supporting Mine Reclamation: A Case Study Of Mae Moh Mine In Lampang Province, Thailand, Tejendra K. Yadav, Polpreecha Chidburee, Nattapon Mahavik

Applied Environmental Research

Detailed, accurate, and frequent mapping of land cover are the prerequisite regarding areas of reclaimed mines and the development of sustainable project-level for goals. Mine reclamation is essential as the extractive organizations are bounded by-laws that have been established by stakeholders to ensure that the mined areas are properly restored. As databases at the mines area become outdated, an automated process of upgrading is needed. Currently, there are only few studies regarding mine reclamation which has less potential of land cover classification using Unmanned Aerial Vehicle (UAV) photogrammetry with Deep learning (DL). This paper aims to employ the classification of …


Quantifying Avoidable Food Waste And Identifying Its Underlying Causes: A Case Study Of A University Dormitory In Thailand, Shimpei Iwasaki, Suphat Prasopsin, Thamarat Phutthai Jan 2021

Quantifying Avoidable Food Waste And Identifying Its Underlying Causes: A Case Study Of A University Dormitory In Thailand, Shimpei Iwasaki, Suphat Prasopsin, Thamarat Phutthai

Applied Environmental Research

To develop well-planned and effective policies and programs for reducing avoidable food waste, it is important to quantify the actual food waste level in particular settings and assess relationships among consumers’ awareness, attitudes, and behaviors. Recognizing these considerations, this paper measured avoidable food waste generated by university students living in dormitory buildings and identified its underlying causes in the case of Kanchanaburi campus, Mahidol University, Thailand. The study applied a food waste composition survey 18 times between January and May 2019 while administering questionnaires in October 2019 to the dormitory students. Based on these measures, the study identified 1,417 instances …


Environmental Degradation-Education Nexus In Malaysia, Wong Sing Yun Jan 2021

Environmental Degradation-Education Nexus In Malaysia, Wong Sing Yun

Applied Environmental Research

This study aims to examine the role of education on CO2 emissions in Malaysia from 1974 to 2014. The unit root tests indicated that the variables were integrated in the same order. As such, the Johansen Co-integration Approach can be employed in this empirical analysis to analyze the impacts of the selected variables. The long-run estimation revealed that economic growth (GDP) and energy consumption (ENERGY) has a negative effect on CO2 emissions. Meanwhile, secondary school education (EDU) demonstrated a significant positive relationship with environmental degradation in the long-run. This can be inferred that secondary school education has a negative effect …


Magnetic Sensors And Geometrical Magnetoresistance: Areview, Abdelfattah Mohammed Mansour Dec 2020

Magnetic Sensors And Geometrical Magnetoresistance: Areview, Abdelfattah Mohammed Mansour

Journal of Metals, Materials and Minerals

Magnetic sensing devices are of the extremely significant kind of detectors, that are used several important and useful applications. Geometrical extraordinary magnetoresistance (EMR) is thegeometrical kind of magnetoresistance associated with the non-magnetic semiconductor-metalhybrid structure and influenced by geometrical shape. As a result of Lorentz force, the current path change from metal (in absence of magnetic field) to semiconductor (under the subjection of themagnetic field) in semiconductor-metal hybrid structure is the key of EMR phenomena, i.e. once the metal is placed in a semiconductor, it works as a short circuit with the majority of applied current moving through metallic inhomogeneity and …


Quenched And Tempered High Strength Steel:A Review, Gadadhar Sahoo, Krishna Kumar Singh, Vinod Kumar Dec 2020

Quenched And Tempered High Strength Steel:A Review, Gadadhar Sahoo, Krishna Kumar Singh, Vinod Kumar

Journal of Metals, Materials and Minerals

Quenched and tempered steel are broadly classified as low alloy conventional grades with C contentof 0.15-0.40% and tool steels with C content as high as 2% alloyed with strong carbide forming elementssuch as Cr, V, Mo etc. in the range of 1-12%. In both the cases, steels are used in hardened/quenchedand tempered or auto tempered condition for improved toughness, strength and wear resistance. The C content and tempering temperature are optimized based on desired application. However, achieving high strength/hardness along with adequate toughness is a challenge. The chemistry designis one of the important parts of developing these grades. The judicious …


Characterization Of Tio2-Activated Carbon Onto Adsorption And Photocatalytic Propertiesand Its Application, Mark Chobchun, Pasakorn Jutakridsada, Puttiporn Thiamsinsangwon, Pornnapa Kasemsiri, Khanita Kamwilaisak, Prinya Chindaprasirt Dec 2020

Characterization Of Tio2-Activated Carbon Onto Adsorption And Photocatalytic Propertiesand Its Application, Mark Chobchun, Pasakorn Jutakridsada, Puttiporn Thiamsinsangwon, Pornnapa Kasemsiri, Khanita Kamwilaisak, Prinya Chindaprasirt

Journal of Metals, Materials and Minerals

This study investigates the characterization of TiO2in conjunction with activated carbon(AC) on its adsorption and photocatalytic properties. TiO2in theabsence and presence of AC were preparedby the sol-gel method. TiCl4was used as a precursor to reduce using acidic solution during preparationprocess. The effects of the amount of AC on the characteristics of composites were investigated. TGA technique was used to evaluate the amount of TiO2and AC in TiO2/AC composite. The adsorptionproperties of TiO2/AC were characterized using XRD, TEM, N2adsorption/desorption, FTIR and UV - Visdiffuse reflectance spectroscopy techniques. The photocatalytic activitiesof the composites were investigated by measuring the removal of acid dye. …


Screen Printed Textile Electrodes Using Graphene And Carbon Nanotubes With Silver For Flexible Supercapacitor Applications, Norawich Keawploy, Radhakrishnan Venkatkarthick, Panyawat Wangyao, Jiaqian Qin Dec 2020

Screen Printed Textile Electrodes Using Graphene And Carbon Nanotubes With Silver For Flexible Supercapacitor Applications, Norawich Keawploy, Radhakrishnan Venkatkarthick, Panyawat Wangyao, Jiaqian Qin

Journal of Metals, Materials and Minerals

The eco-friendly conductive cotton textile is promising alternatives for the flexible substrates in wearable devices since the cotton is as an inexpensive natural fabric material and compatible in modern portable electronics with adequate electrical conductivity. In this work, flexible conductive cotton-based electrodes areprepared via a screen-printing method using the carbonaceous nanomaterialssuch as carbon nanotubes (CNTs) and graphene with an additional component of conductive silver (Ag) powder and textile ink. The prepared conductive cotton electrodes exhibit lower sheet resistance (<10Ω) along with superior mass loading (20-30mgcm-2). On the basis of the performance of cottonelectrodes prepared, an all-solid-state flexible supercapacitor device was successfully fabricated whichexhibits a high specific areal capacitance of 677.12 mFcm-2at 0.0125 mAcm-2 for a suitable electrodecomposition (60% of Ag and 40% CNTs) using a PVA-KOH gel electrolyte. The flexible device endures a stable electrochemical performance under severe mechanical deformation using differentbending angles (0, 30, 45, 60and 90) of the device and possesses excellent cyclic stability with the capacitance retention of ~80% even after 3000 CV cycles.


The Usage Of Coal−Layered Double Oxide For Removal Of Toxic Dye Fromaqueous Solution, Pornnapa Tongchoo, Sonchai Intachai, Prakaidao Pankam, Chomponoot Suppaso, Nithima Khaorapapong Dec 2020

The Usage Of Coal−Layered Double Oxide For Removal Of Toxic Dye Fromaqueous Solution, Pornnapa Tongchoo, Sonchai Intachai, Prakaidao Pankam, Chomponoot Suppaso, Nithima Khaorapapong

Journal of Metals, Materials and Minerals

CoAl−layered double oxide derived from calcination of CoAl−layered double hydroxide at400Cfor 120 min, delivered the change in microstructure with increasing surface area. Spinel Co3O4was the majority in the product as confirmed by X-ray diffraction, and Fourier transform infrared andUV-visible spectroscopies. The calcined product, CoAl−layered double oxide resulted in significantadsorption capacity on dye removal superior to that of CoAl−layered double hydroxide. The adsorbed amounts of the diverse dyes increased as follows: methylene blue phenolphthaleinmethyl orange orange II. The adsorption affinity between adsorbent and dyes relied on electrostatic interaction and physical adsorption.


Soldering Of Copper Using Graphene-Phosphoric Acid Gel, Gurudatt Puranik, Asis Sarkar, Nirankar Mishra, Sangam Chandrasekhar Gurumurthy, Shridhar Mundinamani Dec 2020

Soldering Of Copper Using Graphene-Phosphoric Acid Gel, Gurudatt Puranik, Asis Sarkar, Nirankar Mishra, Sangam Chandrasekhar Gurumurthy, Shridhar Mundinamani

Journal of Metals, Materials and Minerals

Soldering is a physical process in which one metal melts and joins the other to form a strong bond,which further helps in electron conduction and increases the mechanical strength in any electronic circuits. The present work demonstrates the development of graphene-based flux comprising of 2 g of graphene and 2 ml of phosphoric acid for the residue-free, high stability, durable, and two-stepsoldering of copper wire on to the surface of the copper-based printed circuit board. The soldering fluxcan be applied to the copper, and wire can be soldered in ambient conditions using commercial solderingiron at a standard soldering temperature of …


Laser Powder Bed Fusion Of Ti6al4v Lattice Structures And Their Applications, Thywill Cephas Dzogbewu Dec 2020

Laser Powder Bed Fusion Of Ti6al4v Lattice Structures And Their Applications, Thywill Cephas Dzogbewu

Journal of Metals, Materials and Minerals

The study focused on producing lattice structures using rhombic and diagonal nodes and indicatingtheir logical biomedical and engineering applications. Laser powder bed fusion manufacturingtechnology a subset of additive manufacturing was used to manufacture the lattice structures with different struts geometry. Average elastic modulus value of 5.30.2 GPa was obtained for therhombic lattice structures and 5.10.1 GPa for the diagonal lattice structures. Generally, the mechanicalproperties of the lattice structures produced could be logically considered suitable for biomedical and engineering applications. The mechanical properties of the lattice structures could be fine-tunedfor a specific engineering or biomedical applications by varying the lattice properties …


Preparation And Properties Of Fired Clay Bricks With Added Wood Ash, Anuwat Srisuwan, Supachai Sompech, Chiawchan Saengthong, Sukhontip Thaomola, Prinya Chindraprasirt, Nonthaphong Phonphuak Dec 2020

Preparation And Properties Of Fired Clay Bricks With Added Wood Ash, Anuwat Srisuwan, Supachai Sompech, Chiawchan Saengthong, Sukhontip Thaomola, Prinya Chindraprasirt, Nonthaphong Phonphuak

Journal of Metals, Materials and Minerals

This study was designed to determine the effects of wood ash on the physical and mechanical properties of fired clay bricks. The clay bricks were fabricated with the addition of 0, 4, 8, 12, and 16% by weight of wood ash. Strength development of brick was cased byfired at 900, 1000, and 1100°C for 40 min. The experimental results demonstrated that the physical property and strength of the fired clay bricks depend on the wood ash contentand firing temperature. Higher wood ash content affected an increase in porosity and water absorption, while the bulk density of the clay brickswas reduced. …


Ultraviolet‐Shielding And Water Resistance Properties Of Graphene Quantum Dots/Polyvinyl Alcohol Composite-Based Film, Sutthipoj Wongrerkdee, Pichitchai Pimpang Dec 2020

Ultraviolet‐Shielding And Water Resistance Properties Of Graphene Quantum Dots/Polyvinyl Alcohol Composite-Based Film, Sutthipoj Wongrerkdee, Pichitchai Pimpang

Journal of Metals, Materials and Minerals

The Ultraviolet‐shielding (UV‐shielding) and water resistance properties of graphene quantum dots/polyvinyl alcohol (GQDs/PVA) composite-based film have been investigated. The GQDs/PVA composite-based films were fabricated with different GQDs concentrations of 0, 5, 10, 15, and 20 wt%. The optical property of GQDs was carried out by utilizing fluorescence spectroscopy. Characterizationsof GQDs/PVA composite-based films were performed byusing FT-IR spectroscopy, and UV-vis spectroscopy. It was found that GQDs exhibited the strongest excitation wavelength in the UV range. GQDs/PVA composite-based films offered an improved UV-shielding capacity when compared to PVA films and glass. Particularly, the GQDs/PVA composite-based film containing 20 wt% GQDs exhibited a …


Impact Of Boron Carbide And Graphite Dual Particulates Addition On Wear Behavior Of A356 Alloy Metal Matrix Composites, Pankaj R. Jadhav, Madeva Nagaral, Shivakumar Rachoti, Jayasheel I. Harti Dec 2020

Impact Of Boron Carbide And Graphite Dual Particulates Addition On Wear Behavior Of A356 Alloy Metal Matrix Composites, Pankaj R. Jadhav, Madeva Nagaral, Shivakumar Rachoti, Jayasheel I. Harti

Journal of Metals, Materials and Minerals

The current work gives the detailed microstructural analysis and wear behaviour of aluminiumalloy A356 based metal matrix composite. Here, boron carbide (B4C) and graphite (Gr) particulates were used as reinforcing phase to develop A356/ 4 wt% B4C, A356/ 4 wt% Gr composites along with A356/ 4 wt% Gr/ 12 wt% B4C hybrid composites. The composites were developed by conventional stir casting method to improve the wear properties. The developed composites were subjected to scanning electron microscope (SEM) formicrostructural analysis and then to DUCOM made wear test assembly to know the dry sliding wear behaviour. The wear tests were conducted for …