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2024

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Articles 9211 - 9226 of 9226

Full-Text Articles in Engineering

Photoluminescent Carbon Nanodots For Artificial Photosynthesis, Rajie A. Medina, Michael E. Franco, Lyn Marie De Juan-Corpuz, Ryan D. Corpuz Jan 2024

Photoluminescent Carbon Nanodots For Artificial Photosynthesis, Rajie A. Medina, Michael E. Franco, Lyn Marie De Juan-Corpuz, Ryan D. Corpuz

Journal of Metals, Materials and Minerals

The emerging field of carbon dots (CDs), a type of carbon nanostructure that has gained significant attention due to its unique properties and potential applications. CDs possess remarkable attributes, including photoluminescence, electrochemical potential, compatibility with living organisms, solubility in water, chemical stability, and versatile surface properties. The chemical structure, particle size, and surface functionalities of CDs all have an impact on their photoluminescent properties, which are the focus of this review. The photoluminescence mechanism in CDs is discussed, highlighting their amorphous structure, and comparing them to graphene quantum dots. The paper delves into the application of CDs in artificial photosynthesis, …


Hot Corrosion Behavior Of Mg2 Sio4 Ceramic Exposed To Molten Na2so4 At 900℃ To 1100℃, Hamza Milles, Louafi Snani, Amel Oulabbas, Khaled Toualbia Jan 2024

Hot Corrosion Behavior Of Mg2 Sio4 Ceramic Exposed To Molten Na2so4 At 900℃ To 1100℃, Hamza Milles, Louafi Snani, Amel Oulabbas, Khaled Toualbia

Journal of Metals, Materials and Minerals

Thermal barriers are used as protective coating for critical components working at high temperature of gas turbines. Forsterite (Mg2SiO4) ceramic is proposed by researchers as a novel thermal barrier coating (TBC), due to its low thermal conductivity and good thermal expansion. Hot corrosion results from the molten salts effect on the TBC’s surface, accumulated during the combustion processes. In this study, Mg2SiO4 samples were exposed to Na2SO4 molten salt at 900℃, 1000℃ and 1100℃ for 6 h in air. Samples were investigated and compared using scanning electron microscope (SEM) and X-Ray diffractometer (XRD). MgSO4 was the predominant corrosion product observed …


A Contribution To The Exploration Of The Chemical Durability, Thermal Stability, And Structural Ability Of Glasses From The Fe2o3-K2o-Moo3-P2o5 Quaternary System, Asmae Er-Rafai, Yasmina Alaoui, Mohamed Laourayed, Mohamed Ounacer, Mouloud El Moudane, Mohammed Sajieddine, Abdelkbir Bellaouchou Jan 2024

A Contribution To The Exploration Of The Chemical Durability, Thermal Stability, And Structural Ability Of Glasses From The Fe2o3-K2o-Moo3-P2o5 Quaternary System, Asmae Er-Rafai, Yasmina Alaoui, Mohamed Laourayed, Mohamed Ounacer, Mouloud El Moudane, Mohammed Sajieddine, Abdelkbir Bellaouchou

Journal of Metals, Materials and Minerals

The relationships between the properties and structure of xFe2O3-(40-x)K2O-10MoO3-50P2O5 glasses have been reported in this paper. Homogeneous glasses are formed for different Fe2O3 contents. The density and molar volume evolution of these glasses shows that Fe2O3 acts as a glass former and strengthens the structural bonds of the glass. Experimental 57Fe Mössbauer spectroscopy graphs suggest the existence of divalent Iron (FeII) and trivalent Iron (FeIII). The boost in chemical durability agrees with the growth in glass transition temperature due to more powerful bonding in the structural network. P-O-Fe bonds replace P-O-P bonds when Fe2O3 is present in the phosphate network.


Composition-Driven Phase Coexistence And Functional Properties Of The (1-X)Bzt-(X)Bct Ceramics Near The Phase Convergence Region, Jirapa Tangsritrakul, Chumpon Wichittanakom, Chatree Saiyasombat Jan 2024

Composition-Driven Phase Coexistence And Functional Properties Of The (1-X)Bzt-(X)Bct Ceramics Near The Phase Convergence Region, Jirapa Tangsritrakul, Chumpon Wichittanakom, Chatree Saiyasombat

Journal of Metals, Materials and Minerals

The concept of composition-induced phase transformation in Lead Zirconate Titanate (PZT) at the Morphotropic Phase Boundary (MPB) has been employed to improve functional properties of the (1-x)BZT-(x)BCT ceramic. However, it was observed that the phase diagram of the (1-x)BZT-(x)BCT ceramic is different to the PZT. As a result, the nature of the superior functional properties found in (1-x)BZT-(x)BCT ceramic is unlike PZT and still unclear so far. In this work, functional properties; dielectric, ferroelectric, energy storage, and piezoelectric properties, of the (1-x)BZT-(x)BCT ceramics where x = 0.3 mol% to 0.6 mol% were evaluated at room temperature in comparison to the …


Incorporating Novel Bio-Mineral Materials Of Silicone-Arrowroot Modified Starch For Compressed Powder, Pirada Sudprasert, Ananthaya Sansawat, Piangkhwan Kruapoo Jan 2024

Incorporating Novel Bio-Mineral Materials Of Silicone-Arrowroot Modified Starch For Compressed Powder, Pirada Sudprasert, Ananthaya Sansawat, Piangkhwan Kruapoo

Journal of Metals, Materials and Minerals

Incorporating novel bio-mineral materials of silicone-arrowroot modified starch (SA) is an environmentally friendly technique to create compressed powder, thereby integrating biodiversity with sustainability and responding to the Bio-Circular-Green (BCG) economy. The SA had improved flowability and water resistance compared with non-modified arrowroot flour (A0), concurring with the Fourier Transform Infrared (FTIR), scanning electron microscope (SEM) analyses that indicated more hydrophobic properties. To investigate the formulated dust and compressed powder, three types of binders including magnesium stearate (Ms), isopropyl myristate (Im), and mineral oil (Mo) were examined. Powder samples of all binders at each concentration gave high water resistance with floating …


Lldpe Film Development Surface With Nucleating Agents To Reduce Fat Stains From Food Adherence On The Film Surface For Easy Rinsing Before Recycling, Nattapong Pinpru, Chiranicha Ninthap, Supang Sripraphot, Supharada Khaisaat Jan 2024

Lldpe Film Development Surface With Nucleating Agents To Reduce Fat Stains From Food Adherence On The Film Surface For Easy Rinsing Before Recycling, Nattapong Pinpru, Chiranicha Ninthap, Supang Sripraphot, Supharada Khaisaat

Journal of Metals, Materials and Minerals

The purpose of this research was to enhance the surface of linear low-density polyethylene (LLDPE) film by using single and hybrid nucleating agents to reduce fat stains from food adherence on the film surface for easy rinsing before recycling, consequently reducing energy consumption before recycling. The process begins with the preparation of a high-concentration masterbatch of LLDPE with nucleating agents and polyethylene glycol (PEG), followed by blown film and test analysis. The results showed that both single and hybrid nucleating agents resulted in substantial modifications in the surface characteristics of the film. The altered surface texture of the film makes …


The Effects Of Copper On The Mechanical Properties Of Ti-10mo Alloy Prepared By Powder Metallurgy Method, Aji Abdillah Kharisma, Haris Rudianto, Achmad Benny Mutiara, Sulistyo Puspitodjati, Fahamsyah Hamdan Latief, Agus Sukarto Wismogroho, Wahyu Bambang Widayatno, Didik Aryanto, Cherly Firdharini Jan 2024

The Effects Of Copper On The Mechanical Properties Of Ti-10mo Alloy Prepared By Powder Metallurgy Method, Aji Abdillah Kharisma, Haris Rudianto, Achmad Benny Mutiara, Sulistyo Puspitodjati, Fahamsyah Hamdan Latief, Agus Sukarto Wismogroho, Wahyu Bambang Widayatno, Didik Aryanto, Cherly Firdharini

Journal of Metals, Materials and Minerals

Titanium alloys are currently widely explored and produced for applications in various engineering fields. Alloying metal elements such as Mo, Cu, and Mn bring more advantages among them to help improve the mechanical properties of titanium alloys. This study is intended for the evaluation of mechanical properties through compression and hardness testing performed on a Ti-10Mo alloy with copper addition by powder metallurgy. Ti-10Mo alloys with the addition of copper contents of 3 wt% Cu, 6 wt% Cu, and 9 wt% Cu were prepared to optimize the properties of Ti-10Mo-xCu alloys. With the addition of 3 wt% copper, the compressive …


Fast Microwave Synthesis Of High-Silica Natural Soil Based Porous Geopolymer, Naritsara Toobpeng, Sirithan Jiemsirilers Jan 2024

Fast Microwave Synthesis Of High-Silica Natural Soil Based Porous Geopolymer, Naritsara Toobpeng, Sirithan Jiemsirilers

Journal of Metals, Materials and Minerals

This study describes a simple microwave process for fabricating porous geopolymer-polymer based Shirasu soil. The porous geopolymer samples were synthesized using sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) solution as alkaline solution in range of 0.5 M to 9 M. After mixing process, the geopolymer slurry was heated and stimulated geopolymerization reaction by different microwave powers at 200 W, 500 W and 700 W for 30 s, 60 s, 90 s and 120 s. The influence of NaOH concentration, microwave powers and heating times on the apparent bulk density, the water adsorption was focused. Results showed that the microwave powers …


First-Principles Study On Structural And Electronic Properties Of P3ht-Graphene, Fia Amalia, Ari Dwi Nugraheni, Sholihun Sholihun Jan 2024

First-Principles Study On Structural And Electronic Properties Of P3ht-Graphene, Fia Amalia, Ari Dwi Nugraheni, Sholihun Sholihun

Journal of Metals, Materials and Minerals

Based on density functional theory, calculations have been carried out to study the structural and electronic properties of the polymer Poly (3-hexylthiophene) (P3HT) interacting with monolayer graphene as an active layer. (P3HT)1-graphene and (P3HT)2-graphene are optimized on graphene using the generalized-gradient-approximation type of the exchange-correlation functional. Adsorption energy, band gap, and charge transfer are calculated. The calculated adsorption energy shows that all systems have negative adsorption energy, indicating that the reaction is exothermic. Compared to (P3HT)1-graphene, (P3HT)2-graphene has a lower band gap. As for the charge transfer calculation, a negative ΔN indicates that electron transfers from P3HT to graphene.


Integration Of Jackfruit Seed-Derived Carbon Dots And Electronic Nose For A Sensitive Detection Of Formaldehyde Vapor, Thitarat Prathumsuwan, Sumana Kladsomboon, Alfred Antony Christy, Insik In, Xiao Liang, Shufeng Song, Yao Wang, Thitirat Inprasit, Peerasak Paoprasert, Natee Sirisit Jan 2024

Integration Of Jackfruit Seed-Derived Carbon Dots And Electronic Nose For A Sensitive Detection Of Formaldehyde Vapor, Thitarat Prathumsuwan, Sumana Kladsomboon, Alfred Antony Christy, Insik In, Xiao Liang, Shufeng Song, Yao Wang, Thitirat Inprasit, Peerasak Paoprasert, Natee Sirisit

Journal of Metals, Materials and Minerals

The preparation of carbon dots from jackfruit seeds through a pyrolysis method at 280℃ and their use for the detection of formaldehyde were reported. The as-prepared carbon dots showed a high fluorescence efficiency with a quantum yield of 12.7% and excellent photostability and dispersibility in aqueous solution with a zeta potential of ‒62.5 mV. The integration of carbon dot thin film and a home-made optical electronic nose system possessed sensitivity towards formaldehyde vapor with a detection limit of 24.7%v/v across a linear range of 25%v/v to 100%v/v. Furthermore, the sensor showed the highest sensitivity towards formaldehyde against other volatile organic …


Nano-Zno Prepared By Using Chaya And Mango Leaves Extract For Photocatalyst Of Methylene Blue, Sri Wahyu Suciyati, Junaidi Junaidi, Rudy Situmeang, Posman Manurung Jan 2024

Nano-Zno Prepared By Using Chaya And Mango Leaves Extract For Photocatalyst Of Methylene Blue, Sri Wahyu Suciyati, Junaidi Junaidi, Rudy Situmeang, Posman Manurung

Journal of Metals, Materials and Minerals

This research aimed to synthesize nano-ZnO from chaya (Cnidoscolus aconitifolius) and mango leaves extract (Mangifera indica) as environmentally friendly photocatalysts. Nano-ZnO was synthesized using green synthesis, with leaves extracts as reducing agents and nanoparticle size stabilizers. The samples were prepared using two methods, namely nano-ZnO-1 and nano-ZnO-2. The results of Fourier transform infrared spectroscopy (FTIR) analysis showed the contribution of metabolite compounds in nano-ZnO synthesis. X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed the crystal size in nano range, with spherical nanorod morphology observed. Ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) determined the band gap energy …


Investigating The High-Impact Deformation Behavior Of Induced-Nano Precipitation Hardened In718 Alloy, Harrison Okechukwu Onovo, Muideen Adebayo Bodude, David Ehigie Esezobor, Thaddeus Tochukwu Akano Jan 2024

Investigating The High-Impact Deformation Behavior Of Induced-Nano Precipitation Hardened In718 Alloy, Harrison Okechukwu Onovo, Muideen Adebayo Bodude, David Ehigie Esezobor, Thaddeus Tochukwu Akano

Journal of Metals, Materials and Minerals

Superalloys are the preferred materials for modern high-rotational complex components due to their exceptional ability to maintain critical properties such as strength, oxidation/corrosion resistance, even under extreme temperatures and dynamic impacts. This study investigates the dynamic impact response of nanoprecipitation-hardened 718 alloy (NPH-718 alloy) under various loading conditions. The wrought nickel-based NPH-718 alloy was transformed into a nanostructured state through a precise heat treatment process involving controlled cooling rates (28℃∙s‒1 to 30℃∙s‒1). A mechanical compression test, leading to failure, was employed to assess the alloy's ability to withstand dynamic impacts. The compressive dynamic behavior of the alloy at high strain …


Atmospheric Hydrochloric And Nitric Acid Leaching Of A Limonite Ore From The Wolo Mine Area, Southeast Sulawesi, Indonesia, Sufriadin -, Malyanus Yepta, Irzal Nur, Purwanto -, Rizky Amalia, Ulva Ria Irfan, Djabal Nur Basir, Tsubasa Otake Jan 2024

Atmospheric Hydrochloric And Nitric Acid Leaching Of A Limonite Ore From The Wolo Mine Area, Southeast Sulawesi, Indonesia, Sufriadin -, Malyanus Yepta, Irzal Nur, Purwanto -, Rizky Amalia, Ulva Ria Irfan, Djabal Nur Basir, Tsubasa Otake

Journal of Metals, Materials and Minerals

The atmospheric acid leaching studies of a limonite ore sample from the Wolo mine area, Southeast Sulawesi, Indonesia, have been performed using hydrochloric acid (HCl) and nitric acid (HNO3). The objectives of these studies were to compare the leaching degree of metals (Ni, Co, Fe, and Al) and to analyze the dissolution behavior of minerals under different acid concentrations. Mineralogical characterization of the ore sample was conducted using optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction, whereas chemical composition was determined by X-ray fluorescence (XRF) spectrometry and atomic absorption spectroscopy (AAS), respectively. An atmospheric leaching test was done with …


Photocatalytic Degradation Of Ciprofloxacin Drug Utilizing Novel Pvdf/Polyaniline/ Lanthanum Strontium Manganate@Ag Composites, Swayam Aryam Behera, Ali Amanat, P. Ganga Raju Achary Jan 2024

Photocatalytic Degradation Of Ciprofloxacin Drug Utilizing Novel Pvdf/Polyaniline/ Lanthanum Strontium Manganate@Ag Composites, Swayam Aryam Behera, Ali Amanat, P. Ganga Raju Achary

Journal of Metals, Materials and Minerals

Poly (vinylidene fluoride) (PVDF) is the first-choice ferroelectric support or membrane material. The lanthanum strontium manganite (LSMO) is a well-known electrode material in the class of the solid oxide fuel cell (SOFC) materials. A set of four polymer composites PVDF-LSMO-PANI(5.0 wt%) with different amount of silver doping were fabricated with the silver nitrate and reducing agent. The characterization of these four novel PVDF based composites were characterized by the XRD, FTIR, SEM, UV-Visible DRS. The present communication highlights: (I) the effect of PANI in the PVDF-LSMO-PANI (PLP) composites towards the photocatalytic degradation of ciprofloxacin drug. (II) the effect of Ag …


The Effect Of Two-Stage Heat Treatment On The Microstructure And Mechanical Properties Of High Chrome Austenitic Manganese Steel, Mohammad Reza Hermawan, Budi Hartono Setiamarga, Ilham Nur Hakim, Rizka Mulia Anggraeni Jan 2024

The Effect Of Two-Stage Heat Treatment On The Microstructure And Mechanical Properties Of High Chrome Austenitic Manganese Steel, Mohammad Reza Hermawan, Budi Hartono Setiamarga, Ilham Nur Hakim, Rizka Mulia Anggraeni

Journal of Metals, Materials and Minerals

In this research, heat-treatment was used to determine changes in the microstructure and mechanical characteristics of austenitic manganese steel equivalent to ASTM A128-C. Carbide formed in as-cast conditions is transformed into dispersed hardened austenite to increase the toughness of the material because it can inhibit dislocation movement. Heat treatment is carried out in two heating stages. The first stage of heating was carried out at a temperature of 625°C with a holding time varying by 2.5, 3.5, and 4.5 h, and the second stage was carried out at a temperature of 1000°C with a constant holding time of 1.5 h. …


In Vitro And Vivo Biocompatibility And Degradability Of Low-Alloyed Mg-Zn-Ca-Mgo Composite As Bone Repair Biomaterials, Shuquan Zhang, Jiangtao Feng, Chaokun Tang, Ran Pang, Xinglong Zhang, Chenguang Li, Weihao Zhang, Fengxin Zhou, Feng Xue, Shaoyuan Lyu, Minfang Chen, Hao Wang Jan 2024

In Vitro And Vivo Biocompatibility And Degradability Of Low-Alloyed Mg-Zn-Ca-Mgo Composite As Bone Repair Biomaterials, Shuquan Zhang, Jiangtao Feng, Chaokun Tang, Ran Pang, Xinglong Zhang, Chenguang Li, Weihao Zhang, Fengxin Zhou, Feng Xue, Shaoyuan Lyu, Minfang Chen, Hao Wang

Journal of Metals, Materials and Minerals

Magnesium alloys have gained attention as biodegradable bone repair biomaterials. Unlike non-biodegradable materials like titanium and tantalum, biodegradable implants offer advantages in promoting bone healing and minimizing chronic inflammatory reactions. However, the impact of the implant's degradation on the osteogenic environment remains a concern. The Mg-Zn-Ca-MgO composite, being biocompatible and containing osteogenic ions, is a promising candidate. This study assesses the degradability and in vitro/in vivo biocompatibility of two Mg-Zn-Ca-MgO composites with varying degradation rates. The Mg-1Zn-0.2Ca-1.0MgO composite was prepared, and leaching solutions were created following standard protocols. MC3T3-E1 cell cultures were conducted to assess cell toxicity, alkaline phosphatase (ALP) …