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Journal of Metals, Materials and Minerals

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Facile Purification Of Locally Mined Gypsum And Its Use For Preparing Nano-Hemihydrates, Luqman Ayodeji Adams, Enobong Essien, Taiwo Aiyeloro, Stella Oseyomon, John Makanjuola Jan 2021

Facile Purification Of Locally Mined Gypsum And Its Use For Preparing Nano-Hemihydrates, Luqman Ayodeji Adams, Enobong Essien, Taiwo Aiyeloro, Stella Oseyomon, John Makanjuola

Journal of Metals, Materials and Minerals

Gypsum has a wide range of applications, in interior decorations, building construction, supplements or implants in orthopaedics to mention a few. However, in many developing countries including Nigeria, there is still a large-scale importation despite huge available natural deposits. In this study, a facile method to purify locally-mined gypsum has been explored based on the mineral retrograde solubility in water. The purified gypsum was investigated for its elemental composition in comparison to the crude sample and a commercially obtained medical-grade gypsum using X-ray fluorescence (XRF). The results showed that the purified gypsum contained 94.05% CaSO4 compared with the crude which …


Efficiency Of 2-Dodecylaminopyridine For The Liquid-Liquid Extraction Of Gold(Iii) From Succinic Acid Medium, Umrao Shep, Rucha Pawar, Balasaheb Arbad Jan 2021

Efficiency Of 2-Dodecylaminopyridine For The Liquid-Liquid Extraction Of Gold(Iii) From Succinic Acid Medium, Umrao Shep, Rucha Pawar, Balasaheb Arbad

Journal of Metals, Materials and Minerals

Extractive recovery of gold(III) from succinic acid solution with high molecular weight amine: 2-dodecylaminopyridine (2-DDAP) as a new extractant in xylene has been investigated. Extraction data indicates that 5 × 10-4 mol⋅L-1 2-DDAP is a very efficient and fast extractant. Gold(III) can be effectively extracted (D = 414.16) with 2-DDAP from 0.04 M succinic acid solution. The equilibrium of gold(III) from aqueous phase of succinic acid with 2-DDAP is achieved within 60 sec. The extraction of gold(III) with 2-DDAP proceed at the interface according to ion pair formation mechanism. The best stripping solution from among the studied ones is the …


Effect Of Dc Power On The Thickness, Hardness And Adhesion Strength Of Ti-51 At% Ni Coated Ti/Tin, Ishiaka Shaibu Arudi, Esah Hamzah, Muhammad Azizi Mat Yajid, Bushroa Abdul Razak Jan 2021

Effect Of Dc Power On The Thickness, Hardness And Adhesion Strength Of Ti-51 At% Ni Coated Ti/Tin, Ishiaka Shaibu Arudi, Esah Hamzah, Muhammad Azizi Mat Yajid, Bushroa Abdul Razak

Journal of Metals, Materials and Minerals

The coating of Ti/TiN was successfully deposited on Ti-51 at% Ni substrates by using direct current (DC) magnetron sputtering technique and the effect of different sputtering power on the thickness, surface hardness and adhesion strength of the coatings were studied. The microstructural characterization was carried out using scanning electron microscope (SEM), energy-dispersive X-ray (EDX) and X-ray diffractometer (XRD). The coating thicknesses were detected and measured using SEM. The surface hardness test was performed using microhardness tester, and the adhesion strength was carried out by scratch testing. The results showed that the TiN crystallites growth orientation, thickness, surface hardness and adhesion …


Developments Of Biodegradable Polymer Based On Polylactic Acid (Pla) With Natural Color Extracts For Packaging Film Applications, Worraphol Nansu, Passarawan Chaiwut, Sukunya Ross, Gareth Ross, Nungruthai Suphrom, Sararat Mahasaranon Jan 2021

Developments Of Biodegradable Polymer Based On Polylactic Acid (Pla) With Natural Color Extracts For Packaging Film Applications, Worraphol Nansu, Passarawan Chaiwut, Sukunya Ross, Gareth Ross, Nungruthai Suphrom, Sararat Mahasaranon

Journal of Metals, Materials and Minerals

This research was interested in the use of natural colorants to replace hazardous synthetic pigments in the plastic polymer industry. The natural colors were selected from local plants indigenous to southeast Asia, which were Hibiscus sabdariffa roselle calyx (RS) and Caesapinia sappan Linn heartwood (SP). Natural colorant extracts were used as additives in poly(lactic acid ) (PLA). These were manufactured using a twin screws extruder and blow film extruder to obtain biodegradable thin films for use as packaging materials. Biodegradable films were characterized by color index, light barrier properties, water vapor transmission (WVTR), morphology, mechanical and chemical properties. The results …


Effects Of Delay Time And Curing Temperature On Compressive Strength And Porosity Of Ground Bottom Ash Geopolymer Mortar, Nattapong Makaratat, Sumrerng Rukzon, Prinya Chindaprasirt Jan 2021

Effects Of Delay Time And Curing Temperature On Compressive Strength And Porosity Of Ground Bottom Ash Geopolymer Mortar, Nattapong Makaratat, Sumrerng Rukzon, Prinya Chindaprasirt

Journal of Metals, Materials and Minerals

This research investigated development of ground bottom ash (GBA) for a new geopolymer material. The compressive strength and porosity of the geopolymer mortar containing GBA were tested. The GBA-based geopolymer mortar mixtures were designed by control liquid to GBA ratio for all tests. Extra water was also used to maintain the workability of geopolymer mortar. The sodium hydroxide (NaOH) concentrations of 10 M and 15 M were used. Furthermore, sodium silicate (Na2SiO3) to sodium hydroxide (NaOH) ratios by mass such as 0.50, 1.50 and 2.50 were also used as alkali activator solutions. Effects of delay time and no-delay time, heat …


A Review Of Rice Husk Silica As A Heterogeneous Catalyst Support, Izzati Nasir, Nadiah Ameram, Arlina Ali, Siti Roshayu Hassan, Nurul Akmar Che Zaudin, Jamil Mohamed Sapari Jan 2021

A Review Of Rice Husk Silica As A Heterogeneous Catalyst Support, Izzati Nasir, Nadiah Ameram, Arlina Ali, Siti Roshayu Hassan, Nurul Akmar Che Zaudin, Jamil Mohamed Sapari

Journal of Metals, Materials and Minerals

The yield of amorphous silica has less residue of mineral content in rice husk (RH) and a high specific surface area through the simple alkaline extraction process at first, then acid precipitation of RH. At this time, the leaching process using alkali and calcination of RH is the best method to acquire amorphous silica with a high surface area. The different temperatures were used for the calcination of RH and continue with sodium hydroxide (NaOH) treatment by using different concentration. The sample titrated using hydrochloric acid (HCl) to extract silica. Pretreatment with acid leaching for the RH was also conducted …


Enhanced Mechanical And Thermal Properties Of Fly Ash-Based Geopolymer Composites By Wollastonite Reinforcement, Khanthima Hemra, Takaomi Kobayashi, Pavadee Aungkavattana, Sirithan Jiemsirilers Jan 2021

Enhanced Mechanical And Thermal Properties Of Fly Ash-Based Geopolymer Composites By Wollastonite Reinforcement, Khanthima Hemra, Takaomi Kobayashi, Pavadee Aungkavattana, Sirithan Jiemsirilers

Journal of Metals, Materials and Minerals

The present study investigated the mechanical and thermal properties of geopolymer composite. The geopolymer composite was prepared by mixing fly ash and wollastonite with the alkaline activator, which was 6 M KOH:K2SiO3 in a mass ratio of 1:1 and a solid:liquid mass ratio of 3:2. The compressive strength at 28 days of geopolymer was 33.3 MPa and possessed the highest strength of 38.3 MPa when 30 wt% wollastonite was added. The flexural strength presented differently whereby it increased from 2.1 MPa to 6.8 MPa. It increased remarkably up to 200% with the addition of 50 wt% wollastonite. The geopolymer composites …


Raman Signal Enhancement Of Low-Cost Metal Sheet Sers With Gold Decoration, Nampueng Pangpaiboon, Kawinphob Phetnam, Sukon Kalasung, Chanunthorn Chananonawathorn, Viyapol Patthanasettakul, Mati Horprathum, Pitak Eiamchai, Noppadon Nuntawong, Saksorn Limwichean Jan 2021

Raman Signal Enhancement Of Low-Cost Metal Sheet Sers With Gold Decoration, Nampueng Pangpaiboon, Kawinphob Phetnam, Sukon Kalasung, Chanunthorn Chananonawathorn, Viyapol Patthanasettakul, Mati Horprathum, Pitak Eiamchai, Noppadon Nuntawong, Saksorn Limwichean

Journal of Metals, Materials and Minerals

Surface Enhance Raman Spectroscopy (SERS) is a sensitive surface creating plasmonic resonance for the Raman scattering. SERS is considered as a powerful technique to enhance the Raman signal, when quantity of sample is limited. Recently, our lab team has discovered a low-cost SERS template fabrication, laser-engraving method, which is suitable with gold nanoparticles decoration. In this work, two different materials, zinc and copper, are used as metal sheet SERS substrate. Gold nanoparticles sputtered with 270 s of sputtering time are used as decorated noble metal. FE-SEM images illustrate the nano-in-microstructure of the engraved metal sheets. The decorated Au nanoparticles are …


Oxidation Behavior Of Sn-1 Wt% Bi Alloy In Air And Deionized Water At Room Temperature, Tanavut Naravuthichai, Patama Visuttipitukul, Sirichai Leelachao, Tachai Luangvaranunt Jan 2021

Oxidation Behavior Of Sn-1 Wt% Bi Alloy In Air And Deionized Water At Room Temperature, Tanavut Naravuthichai, Patama Visuttipitukul, Sirichai Leelachao, Tachai Luangvaranunt

Journal of Metals, Materials and Minerals

Formation of tin oxides on surface Sn-1 wt% Bi alloy lapping plates causes interactions with protrusions of embedded diamond grits, and reduces the efficiency of the lapping process. The rate and type of oxide formation were investigated to understand the problem. Electrochemical analysis was performed to characterize the oxide film thickness, and x-ray photoelectron spectroscopy was performed to characterize the tin oxide species. Oxidation in air at room temperature reaches a thickness of 23 Å after 72 h. Oxidation in deionized water at room temperature has a faster growth rate, and reaches a thickness of 33 Å after 72 h. …


Mechanical Performance Of Woven Carbon Reinforced Epoxy Composites With Varied Orientation Angle, Sweety Ashish Agrawal, Someshwar Bhattacharya Jan 2021

Mechanical Performance Of Woven Carbon Reinforced Epoxy Composites With Varied Orientation Angle, Sweety Ashish Agrawal, Someshwar Bhattacharya

Journal of Metals, Materials and Minerals

The mechanical properties of woven carbon fibre reinforced epoxy composites laminated with different orientation angle in stacking sequence were investigated. Woven fabric layers with different linear density carbon tow have been produced on modified rigid rapier sample loom and impregnated with epoxy by hand lay-up technique for composite preparation. Curing of composite was carried out at room temperature for 2 h. Five different laminar composites were prepared with different orientation angles [(0/0/0/0), 0/+30/-30/0, 0/+45/-45/0, 0/+60/-60/0 and 0/+90/-90/0]. The mechanical properties like tensile, flexural, and impact test) were analysed in both longitudinal and transverse directions. Physical properties such as density and …


Investigation Of Optimum Parameters For Rotary Friction Welding Of Aluminum Round Bars Using Three-Level Factorial Design Methodology, Tanakorn Jantarasricha, Siridech Kunhirunbawon, Montri Wimol Jan 2021

Investigation Of Optimum Parameters For Rotary Friction Welding Of Aluminum Round Bars Using Three-Level Factorial Design Methodology, Tanakorn Jantarasricha, Siridech Kunhirunbawon, Montri Wimol

Journal of Metals, Materials and Minerals

The welding process has been essential to increasing productivity in numerous industries across Thailand. There are several welding processes to choose from, and the welding process to use will be determined by the suitability of the production in that industry. Another important consideration in welding is to keep the mechanical properties of the joint area as close to the parent material workpiece as possible. This research aims to select the optimum parameter for rotary friction welding aluminum round bar AA6063-T5. That is according to the DIN 50125 type B standard test. The optimal condition consists of welding rotational speed, welding …


Synthesis And Optical Properties Of Forsterite Ceramic Pigments Using Mirror Wastes As A Flux, Niti Yongvanich, Natchaya Lithira, Nitchakarn Nuniead, Wanchalerm Chauyarsa Jan 2021

Synthesis And Optical Properties Of Forsterite Ceramic Pigments Using Mirror Wastes As A Flux, Niti Yongvanich, Natchaya Lithira, Nitchakarn Nuniead, Wanchalerm Chauyarsa

Journal of Metals, Materials and Minerals

Cobalt-doped forsterite ceramic pigments based on the formula (Mg2-2xCo2x)SiO4 (x = 0, 0.05, 0.1, 0.2) were synthesized using mirror wastes as a flux. Addition of this flux enhanced forsterite phase formation at lower temperature by as much as 200℃. The resulting pigment particles were in a micron range which is suitable for use in a ceramic glaze. The host structure (Mg2SiO4) could accommodate cobalt cations up to 20 at%. Investigation on the chemical distribution revealed that no chemical species from the flux reacted with pigment grains. Optical properties were examined by UV-vis spectroscopy and colorimetry. Technical performance of the obtained …


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 …


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 …


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 …


Extraction Of Cellulose Nanofibers From Empty Palm Fruit Bunches Via Mechanical Defibrillation, Zi-Qian Tan, Takaomi Kobayashi, Duangdao Aht-Ong Jan 2021

Extraction Of Cellulose Nanofibers From Empty Palm Fruit Bunches Via Mechanical Defibrillation, Zi-Qian Tan, Takaomi Kobayashi, Duangdao Aht-Ong

Journal of Metals, Materials and Minerals

In recent years, there has been an increasing interest in finding alternative material to replace fossil-oil based product due to the environmental concern. Lignocellulosic biomass has emerged as the promising candidate due to its low-cost and sustainability. The objective of this work was to prepare cellulose nanofibers (CNFs) from empty palm fruit bunches (EPFB), which are the waste originating from palm oil industry. Cellulose fibers were first extracted from EPFB by chemical treatment, followed by mechanical disintegration using high-pressure homogenization. Fiber concentration and defibrillation time during mechanical treatment were studied to investigate their effects on the properties of produced nanofibers. …


The Effect Of Phosphogypsum On Stabilizing Clay Soil And Improving Its Properties For Use As Foundation Soil, Mai Yahya Maaitah, Mus'ab Ziad Banat Jan 2021

The Effect Of Phosphogypsum On Stabilizing Clay Soil And Improving Its Properties For Use As Foundation Soil, Mai Yahya Maaitah, Mus'ab Ziad Banat

Journal of Metals, Materials and Minerals

Expansive soil covers large areas in a variety of regions in Jordan which is insufficient to meet the engineering specifications in construction. Phosphogypsum is considered to be the main by-product material which comes from phosphate rock deposits that is available in Jordan. The main purpose of this research is to study the effects of stabilization by phosphogypsum on expansive soil properties. Three Jordanian regions were chosen to represent the expansive soils, Irbid, Madaba, and Abu-Nusire city. Soils were mixed with phosphogypsum at different percentages by dry weight of soil. Some of the representative laboratory tests for swell properties were conducted: …


The Effect Of Artificial Defects On The Fatigue Characteristics Of Aisi 4340 Steel, Yakov B. Unigovski, Dmitry Fishman, Liat Fishman, Liron Shichman, Ofir Moshe, Roni Shneck, Emmanuel Gutman Jan 2021

The Effect Of Artificial Defects On The Fatigue Characteristics Of Aisi 4340 Steel, Yakov B. Unigovski, Dmitry Fishman, Liat Fishman, Liron Shichman, Ofir Moshe, Roni Shneck, Emmanuel Gutman

Journal of Metals, Materials and Minerals

This study examined the fatigue life (Nf) and fatigue limit (FL) of AISI 4340 steel in relation to surface roughness, artificial defects and shot peening. Artificial surface defects on fatigue specimens were obtained by electrical discharge machining (EDM) or by pre-corrosion in 3.5% NaCl and perchloric acid solutions, followed by a fatigue test. The presence of artificial defects of various sizes, taken into account by the area  parameter, led to a significant decrease in fatigue characteristics, while shot peening contributed to their noticeable improvement. Defects resulting from electrochemical corrosion had a much greater negative effect on fatigue …


The Enhancement Of Ethanol Gas Sensors Response Based On Calcium And Zinc Co-Doped Lafeo3/Fe2o3 Thick Film Ceramics Utilizing Yarosite Minerals Extraction As Fe2o3 Precursor, Endi Suhendi, Zeany Luckyta Amanda, Muhamad Taufik Ulhakim, Andhy Setiawan, Dani Gustaman Syarif Jan 2021

The Enhancement Of Ethanol Gas Sensors Response Based On Calcium And Zinc Co-Doped Lafeo3/Fe2o3 Thick Film Ceramics Utilizing Yarosite Minerals Extraction As Fe2o3 Precursor, Endi Suhendi, Zeany Luckyta Amanda, Muhamad Taufik Ulhakim, Andhy Setiawan, Dani Gustaman Syarif

Journal of Metals, Materials and Minerals

A gas sensor is a renewed interest of research which has been developed to make a device that can be detected the harmful gases and applied in the several fields of industries. In this paper, we report the modified of gas sensor based thick film ceramic LaFeO3/Fe2O3 by added calcium and zinc co-doping prepared by screen-printed technique. In this work, yarosite mineral was utilized as Fe2O3 precursor. It aims to take the advantages of abundance natural resources in Indonesia to save a cost in gas sensor fabrication. Then, x-ray diffraction (XRD), scanning electron microscopy (SEM) and electrical properties characterization were …


Wollastonite And Talc Reinforced Polypropylene Hybrid Composites: Mechanical, Morphological And Thermal Properties, Naruedee Putfak, Amnouy Larpkasemsuk Jan 2021

Wollastonite And Talc Reinforced Polypropylene Hybrid Composites: Mechanical, Morphological And Thermal Properties, Naruedee Putfak, Amnouy Larpkasemsuk

Journal of Metals, Materials and Minerals

This study focused on evaluating the mechanical, thermal, and morphological properties of polypropylene (PP) hybrid composites containing two different inorganic mineral fillers, namely wollastonite (WO) and talc. The composites were prepared by melt mixing process using a twin screw extruder and an injection molding machine. All composites contained a constant filler loading at 20 wt% with varying WO/talc weight ratios (20/0, 15/5, 10/10, 5/15, and 0/20). Melt flow index (MFI), mechanical properties (impact strength and tensile properties), heat distortion temperature (HDT) fractured surface morphology, and thermal behaviors of the resulting composites were investigated. The results revealed an enhancement in the …


Effect Of Nitrocarburizing And Argon Admixing On Low Carbon Steel For Component Facility In Radiometallurgical Installation, Erwan Hermawan, Suprapto Suprapto, Usman Sudjadi, Siti Shaleha, Maman Kartaman Ajiriyanto Jan 2021

Effect Of Nitrocarburizing And Argon Admixing On Low Carbon Steel For Component Facility In Radiometallurgical Installation, Erwan Hermawan, Suprapto Suprapto, Usman Sudjadi, Siti Shaleha, Maman Kartaman Ajiriyanto

Journal of Metals, Materials and Minerals

Steel is an important component in the industrialized world with rising growth in world consumption. Steel has wide applications due to its high strength, durability, and cost-effectiveness. This has applications in the nuclear power plant. In Indonesian nuclear industry, low carbon steel is used not only for the fabrication of reactor components but also for the radiometallurgical facilities. However, to avoid the risk of premature failure and enhance the longevity of the components in the service condition, surface modification for the improvement of hardness has been realized. Amongst several methods, surface hardening by following nitrocarburizing has been found to be …


Structural, Magnetic And Transport Properties Of Ca And Sr Doped Lanthanum Manganites, Sunita Keshri, Shailendra Rajput, Sonali Biswas, Leena Joshi, Wojciech Suski, Piotr Wiśniewski Jan 2021

Structural, Magnetic And Transport Properties Of Ca And Sr Doped Lanthanum Manganites, Sunita Keshri, Shailendra Rajput, Sonali Biswas, Leena Joshi, Wojciech Suski, Piotr Wiśniewski

Journal of Metals, Materials and Minerals

This article presents a comparative study for the effect of average A-site cation size on the structural, transport and magnetic properties of Lanthanum manganites. Three polycrystalline colossal magneto-resistive compounds were synthesized using standard solid state reaction method. The electrical resistivity data were analyzed employing standard two-phase model to understand the conduction mechanism. The resistance of polycrystalline ceramic depends on the intragrain resistance (intrinsic resistance) and the intergrain or grain-boundary resistance (extrinsic resistance). The substitution of Sr ions at La-site provides higher magnetic and metal-insulator transitions as compared to Ca ions. The combined substitution of Ca and Sr ions at La-site …


Formation Of Nano-Crystalline Chromium-Zirconium Nitride (Cr-Zr-N) Film Coating By Dc Unbalanced Magnetron Sputtering, Kumpon Leelaruedee, Kattareeya Taweesup, Patama Visuttipitukul Jan 2021

Formation Of Nano-Crystalline Chromium-Zirconium Nitride (Cr-Zr-N) Film Coating By Dc Unbalanced Magnetron Sputtering, Kumpon Leelaruedee, Kattareeya Taweesup, Patama Visuttipitukul

Journal of Metals, Materials and Minerals

This research aimed to improve the properties of chromium nitride (CrN) film coatings by addition of zirconium (Zr) as the third element to form Cr-Zr-N ternary nitride. DC unbalanced magnetron sputtering method was used to form Cr-Zr-N film with various Zr/Zr + Cr atomic ratios.  Mechanical properties, surface morphology and crystal structure of the film were investigated. In the research, Cr-Zr-N film were categorised into 3 types with different Zr amount: low zirconium, (Zr/Zr + Cr = 0.29), medium zirconium (Zr/Zr + Cr = 0.44), and high zirconium (Zr/Zr + Cr = 0.74). All Cr-Zr-N films exhibited nano-crystalline structures with …


Controlled Plasma Tuning Of Mos2 Based Photodetector: From Visible To Ultraviolet Photo Response, Huda Musa Mutlaq, Ali Jabbar Fraih Jan 2021

Controlled Plasma Tuning Of Mos2 Based Photodetector: From Visible To Ultraviolet Photo Response, Huda Musa Mutlaq, Ali Jabbar Fraih

Journal of Metals, Materials and Minerals

Among diverse family of two-dimensional materials, molybdenum disulfide (MoS2) is one of the most promising materials for optical applications thanks to its tunable optical energy bandgap. In this work, a MoS2 based photodetector is fabricated and its optical properties is investigated. With the help of controlled oxygen plasma bombardment, its photoresponse is tuned from visible to ultraviolet region. The photodetector was subjected to three bombardment times of 60 s, 120 s, and 180 s, and it was observed that 180 s irradiation resulted in a change in the optical response range of the photodetector from visible to ultraviolet. In fact, …


Retaining The High-Temperature Phases Of Rb3h(So4)2 And Rb5h3(So4)4 At Room Temperature, Chatr Panithipongwut Kowalski Jan 2021

Retaining The High-Temperature Phases Of Rb3h(So4)2 And Rb5h3(So4)4 At Room Temperature, Chatr Panithipongwut Kowalski

Journal of Metals, Materials and Minerals

The attempts to maintain the higher-temperature phases of Rb3H(SO4)2 and Rb5H3(SO4)4 were demonstrated in this work for the first time. The goal was to explore the possibility to utilize solid acids at lower temperatures while keeping the high-temperature phases which connects to the desirable conductivities. Enabling to do so will allow the ease of handling and thermal cycling, and the energy saving in fuel cell applications, and will allow researchers to study the high-temperature properties of solid acids at lower temperatures without the expenses for the in-situ measurements and the accessibility limitations. The four relatively simple methods, which were the …


Poly(Vinyl)Alcohol Film Composited With Carbon Dots From Water Hyacinth Stalks Based On Gamma Irradiation For The Uv Blocking Film, Tanagorn Kwamman, Threeraphat Chutimasakul, Panida Sangangam, Nattamon Puengposop, Kanokorn Wechakorn Jan 2021

Poly(Vinyl)Alcohol Film Composited With Carbon Dots From Water Hyacinth Stalks Based On Gamma Irradiation For The Uv Blocking Film, Tanagorn Kwamman, Threeraphat Chutimasakul, Panida Sangangam, Nattamon Puengposop, Kanokorn Wechakorn

Journal of Metals, Materials and Minerals

UV-radiation in the range of 200 nm to 400 nm from sunlight can inhibit the photosynthesis process in plants, while visible light in the range of 400 nm to 700 nm promotes photosynthesis and plant growth. In this work, poly(vinyl)alcohol-carbon dots composite film (PVA-CDs film) was developed as a UV-blocking film due to the excellent optical properties of carbon dots and the film-forming properties of PVA. For the synthesis of carbon dots using gamma irradiation, water hyacinth stalk, an invasive aquatic plant, was used as a carbon source. The result showed that PVA-CDs composite film exhibited excellent UV absorption (200 …


Luminescent Properties Of Polyaniline Capped Mn Doped Zns Quantum Dots, Anju Bala, Rajeev Sehrawat, Anil Kumar Sharma, Pardeep Soni Jan 2021

Luminescent Properties Of Polyaniline Capped Mn Doped Zns Quantum Dots, Anju Bala, Rajeev Sehrawat, Anil Kumar Sharma, Pardeep Soni

Journal of Metals, Materials and Minerals

Synthesis of polyaniline capped and Mn doped quantum dots are performed with co-precipitation tech. while structural, optical and morphological properties have been carried out by using Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) study, photoluminescent (PL), absorption spectroscopy and High-Resolution Transmission Electron Microscopy (HR-TEM). Particles size is nearly 2 nm calculated using XRD analysis and nearly 2.5 nm as estimated from HR-TEM study. FTIR spectra confirm that ZnS and polyaniline interact through S-H vibrations. The absorption spectra analysis reflects the occurrence of blue shift at the peak of absorption along with the enhanced band gap of polyaniline capped ZnS(Mn) …


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 …


Eco-Friendly Lake Pigment From Sappanwood: Adsorption Study And Its Application As Natural Colorant For Natural Rubber Toy Balloon, Jitnapa Sirirak, Ployphat Suppharatthanya, Kedsarin Chantha, Sutinee Girdthep, Supanee Chayabutra Jan 2021

Eco-Friendly Lake Pigment From Sappanwood: Adsorption Study And Its Application As Natural Colorant For Natural Rubber Toy Balloon, Jitnapa Sirirak, Ployphat Suppharatthanya, Kedsarin Chantha, Sutinee Girdthep, Supanee Chayabutra

Journal of Metals, Materials and Minerals

Due to the awareness of the impact of synthetic dye on human health and the environment, natural dye and lake pigment have attracted considerable attention from researcher. Herein, pink−red lake pigment from sappanwood was prepared using adsorption approach. The effects of initial pH, pH and concentration of brazilein solution, dosage of aluminium hydroxide, and adsorption time on adsorption were also explored. Results showed that the maximum adsorption capacity of 30 mg g-1 was achieved when 0.25%w/v of aluminium hydroxide and 100 mg L-1 of brazilein solution were applied. The adsorption kinetics and adsorption isotherm fitted the pseudo second order model …