Applied sciences

Archives of Metallurgy and Materials

Content

Archives of Metallurgy and Materials | 2024 | vol. 69 | No 4

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Abstract

Light-powered micromotors are a new type of micromotor that can be used for water purification treatment. This paper focuses on the synthesis processes and its application in water remediation. This mini review will highlight the great potential of these light powered micromotor as well as the significance of preparing them for environmental applications. Photocatalytic micromotors or light-powered micromotors have been intensively researched over the last several years for several applications, such as environmental remediation, biomedicine and micropumps. It has been found that conventional wastewater treatment is commercially inefficient in water remediation. The emphasis then was on a new solution of using micromotor as a potential replacement for water remediation. Many studies have been carried out over the years on the synthesis of these light-powered micromotors, which revolves around the materials used, and applications. This paper, therefore, reflects on the advancement of light-powered micromotors and will be concentrating on the synthesis processes and its application in water remediation. This mini-review will highlight the great potential of these light-driven micromotors as well as the significance of preparing them for environmental applications.
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Authors and Affiliations

M.S. Osman
1 2
M. Ismail
3
K. Khairudin
1 4
M. Fathullah
5 2
ORCID: ORCID
C. Rojviriya
6
N.F. Abu Bakar
6
M.R. Mohd Radzi
1
N. Isa
1

  1. Universiti Teknologi MARA EMZI-UiTM Nanoparticles Colloids & Interface Industrial Research Laboratory (NANO-CORE), Chemical Engineering Studies, College of Engineering, Cawangan Pulau Pinang, Permatang Pauh Campus, 13500 Pulau Pinang, Malaysia
  2. Center of Excellence Geopolymer & Green Technology (CEGeoGTech), 01000 Kangar, Perlis, Malaysia
  3. EMZI Holding Sdn Bhd, H-2, Avenue 2/1, Kedah Halal Park,08000 Sungai Petani, Kedah, Malaysia
  4. Universiti Teknologi MARA Shah Alam, School of Chemical Engineering, College of Engineering, 40450 Shah Alam, Selangor, Malaysia
  5. Universiti Malaysia Perlis (UniMAP), School of Manufacturing Engineering, Pauh Putra Campus, 02600 Arau, Perlis, Malaysia
  6. Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000, Thailand
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Abstract

In the current era, concern about the responsible disposal of industrial waste and its reuse has increased in all societies from the industry. Therefore, the researchers’ institution is focusing its efforts on developing more environmentally friendly products from recycled waste, particularly in the area of sustainable construction. For instance, one of recycled waste is Coal Bottom Ash (CBA), a by-product of coal combustion that is produced in large quantities from thermal power plants. The aims of this study to investigate the physical, chemical and element characteristics of CBA obtained from thermal power plant in Malaysia. Also, CBA compared with cement characteristics to be used as cement replacement in the concrete mixture. Therefore, numerous tests have been performed to investigate CBA’s physical and chemical characteristics. For physical properties such as specific gravity, particle size analysis, fineness modulus, bulk density and loss on ignition. For chemical properties such as X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) in an effort to obtain sustainable materials from thermal power plant waste. Based on the findings in this study, it can be concluded that CBA can be utilized as cement substitute in the production of concrete mixtures.
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Authors and Affiliations

Mohammad I. Al Biajawi
1
R. Embong
1
ORCID: ORCID
M.M. Al Bakri Abdullah
2
ORCID: ORCID

  1. Universiti Malaysia Pahang Al-Sultan Abdullah (UMPSA), Faculty of Civil Engineering Technology, Persiaran Tun Khalil Yaakob, 26300, Pahang, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Geopolymer & Green Technology, Centre of Excellence (CEGeoGTech), Perlis, Malaysia
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Abstract

The publication presents and reviews the results of a physical modelling study of the Cross Wedge Rolling process of ball-studs. The ball-studs was formed in a double system from C45 steel at 1050°C, while the physical modelling process was performed on a scale of 1:2.5 using Primo plasticine as the model material, which was formed at 5°C. For the real tests, steel tools were used, while for the model tests the tools were made of ABS plastic. The experimental tests were followed by measurements of the individual stud steps. The geometrical analysis of the specimens showed that the model material allowed the shape of the forging obtained in the rolling process to be accurately modelled. Based on the physical modelling studies of the Cross Wedge Rolling process of ball-studs, it was concluded that the ball-studs rolling process can be modelled using PRI MO plasticine. Based on the analysis of the physical modelling results obtained, it was concluded that physical modelling allows the Cross Wedge Rolling process to be modelled with a high convergence of the results obtained in real and physical tests.
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Authors and Affiliations

Ł. Wójcik
1
ORCID: ORCID
Z. Pater
1
ORCID: ORCID

  1. Lublin University of Technology, 38 D. Nadbystrzycka Str., 20-618 Lublin, Poland
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Abstract

A waste of electrical power cables becomes a major problem at the present time, so they must be disposed in order to preserve the environment, and to obtain a raw material for the industry with low cost. In this work, recycled materials is prepared by heating up the aluminum wires up to 650°C for melting to prepare the aluminum alloy as a matrix. Then, the matrix reinforced by the nanoparticles (30 nm) of aluminum oxide (Al2O3) to prepare the composite using the stir casting technique. The electrical discharge machining (EDM) as advanced machining, is used to evaluate the materials behavior through the operation. Taguchi method is used to design and determine the suitable input and output factors. The scanning electron microscope (SEM) and hardness are tested before and after machining. The results appeared that improving in microstructure, also the hardness of the composite improved (37.2% and 22.6%) before and after machining.
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Authors and Affiliations

S.H.A. Alfatlawi
1
ORCID: ORCID
N.M. Khabou
2
W.A. Mughir
1

  1. University of Babylon, College of Material’s Engineering, Iraq
  2. University of Sfax, Electromechanical Systems Laboratory (LASEM), National Engineering School of Sfax, BP 1173 3038 Sfax, Tunsia
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Abstract

Pulse-echo ultrasonic test, which is one of the non-destructive testing methods, was used to measure ultrasonic quantities such as longitudinal velocity (VL), shear velocity (VT) and attenuation coefficient (α) in FeCrMn composites. The corresponding elastic constants were determined depending on the longitudinal and transverse velocity. The aim was to reveal the correlation between the microstructural and mechanical properties of FeCrMn composites and ultrasonic quantities. The effect of adding Cr particles on VL and VT velocities is obviously attributed to the change in elastic and shear modulus of FeCrMn composites. It was found that both VL and VT velocities, Young’s modulus (E) and shear modulus (G), as well as hardness values, changed approximately linearly with increasing Cr content. In this study, samples with different volumetric compositions were produced using the powder metallurgy method. It has been revealed that both the applied method and the increase in the amount of Cr have a significant effect on the velocities of VL and VT. The increase in VL and VT is due to the increase of Cr particles, the homogeneous distribution of Cr, the formation of samples especially at a certain temperature, and the decrease of porosity. As a result of these, a decrease in attenuation values was observed depending on the mean grain size. Elastic constants were found to vary in the same way as ultrasonic velocities. By increasing the Cr content both the hardness values and the shear modulus were improved and a good correlation was observed with the grain size.
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Authors and Affiliations

V. Özkan Bilici
1
ORCID: ORCID
A. Yönetken
2
ORCID: ORCID

  1. Afyon Kocatepe University, Physics Dept., 03200, Afyonkarahisar, Turkey Turkey
  2. Afyon Kocatepe University, Engineering Faculty, Electrical Engineering Dept., ANS Campus 03200, Afyonkarahisar, Turkey
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Abstract

The relationship between barrel configurations and porosity of a Ni-based amorphous coating (AM) that is fabricated using a high-velocity air fuel (HVAF) process was revealed by both numerical and experimental methods. A computational fluid dynamics model was applied to investigate the gas-flow field and the behavior of in-flight particles with various barrel configurations. It is found that barrel length obviously affects the particle velocity and temperature while it has a slight influence on the particle velocity and temperature. The longer the barrel length (diameter), the higher the flame (particle) velocity and temperature. By analyzing both particle velocity and temperature, the optimal barrel configuration (4E) to achieve low-porosity coatings was predicted. These calculations were experimentally verified by the production of a low-porosity (2.09%) Ni-based AM that was fabricated by HVAF using the predicted optimal barrel configuration.
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Authors and Affiliations

Nianchu Wu
1
ORCID: ORCID
Tingting Li
1
Xiaotian Su
1

  1. Liaoning Petrochemical University, School of Mechanical Engineering, Fushun, 113001, P.R. China
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Abstract

The study investigated end milling of Inconel 825 with varying spindle speed (N), feed rate (f) and axial depth of cut (da) with Minimum Quality Lubricant (MQL) and flooded lubrication. Molybdenum disulfide (MoS2) with the average particle size of 10 µm was used as lubricating agent. Work considered, center line average of roughness profile as a measure of surface roughness which was measured with a surface roughness tester. Material Removal Rate (MRR) was also measured experimentally using weight difference. The influence of spindle speed (N), feed rate (f) and axial depth of cut (da) during end milling of Inconel 825 on surface roughness and MRR were studied. Prediction of surface roughness by ANOVA linear model for MQL condition was found functionally adequate with R2 = 89.25% which fits with the experimental values. Also, the prediction and optimization of surface roughness using Response Surface Methodology (RSM) was proposed. It was found that, RSM model for MQL condition produced good agreement with the measurement of the given range of input cutting conditions with the prediction capability of 91.66%. Further, the machined surfaces and tool wear were analyzed using Scanning Electron Microscope (SEM) to understand the mechanisms of wear.
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Authors and Affiliations

D. Nathan
1
ORCID: ORCID
T. Ramkumar
1
ORCID: ORCID
M. Selvakumar
2
ORCID: ORCID

  1. Department of Mechanical Engineering, Dr Mahalingam College of Engineering and Technology Pollachi-642003, India
  2. Department of Automobile Engineering, Dr Mahalingam College of Engineering and Technology Pollachi-642003, India
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Abstract

The influence of Ti addition on the microstructure, mechanical properties and electrical conductivity of Cu-14Fe alloy is studied. Great emphasis has been laid on the second phase, texture and mechanical properties. No new phase other than α-Fe phase could be found in Cu-14Fe-0.1Ti alloy using XRD and SEM. With 0.1Ti addition, the distribution of α-Fe phase strip is slightly heterogeneous. Cube, s and brass texture components are largely strengthened in Cu matrix with Ti addition, while copper and goss texture components are rare in Cu matrix of both alloys. In α-Fe phases, α fiber and goss texture components are highly strengthened with Ti addition. It is found that enhanced mechanical properties are achieved in Cu-14Fe-0.1Ti alloy. In detail, with Ti addition, the yield strength and ultimate tension strength increase from 538 and 561 MPa to 580 and 583 MPa, respectively, while maintaining a high value of elongation to failure (6.5%). A lower equivalent grain size and a higher KAM value mainly contributes to the higher yield strengthening effect in Cu-14Fe-0.1Ti alloy. The lower equivalent grain size is derived from the small size distribution range and the small size of Cu matrix in Cu-14Fe-0.1Ti alloy. The dissolution of Ti and formation of nano second phases also improve mechanical properties. However, texture hardly plays a role in the strengthening effect. 0.1Ti addition hardly reduces the electrical conductivity of Cu-14Fe alloy, maintaining a value of 33.43% IACS. The results in this work could provide guidance in texture evolution and property evaluation in Cu-Fe alloys.
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Authors and Affiliations

Huihui Yu
1
ORCID: ORCID
Qiang Hu
1
ORCID: ORCID
Yapan Huang
1
ORCID: ORCID
Yanqi Zeng
1
ORCID: ORCID
Jingxuan Jia
2
ORCID: ORCID
Q. Hu
Rui Hong
3
ORCID: ORCID
Youliang Zhang
1
ORCID: ORCID

  1. Jiangxi Academy Of Sciences, Jiangxi Key Laboratory For Advanced Copper And Tungsten Materials, Nanchang 330096, China
  2. Jiangxi Rare-Earth Academy, Chinese Academy of Sciences, Ganzhou 341000, China
  3. Chongqing University, School of Materials Science And Engineering, Chongqing 400044, China
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Abstract

Cold-pressing method is beneficial in reducing the porosity of geopolymer matrix, but the low liquid volume will result in unreacted aluminosilicate materials. This problem can be resolved by increasing sodium hydroxide (NaOH) concentration. This paper thus investigates the effect of NaOH concentration on the properties of cold-pressed geopolymer. The fly ash was activated by sodium silicate (Na2SiO3) and 10, 12, 14 and 16 M of NaOH solution. The dry mix was compacted with a uniaxial hydraulic press and cured for 7 and 28 days. The specimens were measured by porosity and compressive strength measurements. Scanning electron microscopy (SEM) analysis was performed to determine the microstructure of specimens. The geopolymer was optimized at 14 M NaOH with the highest 28-day compressive strength (109.6 MPa) and lowest porosity (8.1%). The SEM micrographs proved that the geopolymer have a dense and compact microstructure.
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Authors and Affiliations

O. Shee-Ween
1 2
ORCID: ORCID
H. Cheng-Yong
1 3
ORCID: ORCID
M.M.A.B. Abdullah
1 2
ORCID: ORCID
O. Wan-En
1 2
ORCID: ORCID
H. Yong-Jie
1 2
ORCID: ORCID
T. Hoe-Woon
1 3
ORCID: ORCID
L. Jia-Ni
1 2
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Geopolymer and Green Technology, Centre of Excellence (CEGeoGTech), 01000 Kangar, Perlis, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering Technology, 02600 Arau, Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering Technology 02600 Arau, Perlis, Malaysia
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Abstract

This research is part of a continuing effort to synthesize copper and zinc arsenates(III) to use as a zinc dust activator in zinc sulphate solution purification. In this paper, the feasibility of synthesizing crystalline, mono-phase zinc and copper arsenates(III) were investigated. Copper and zinc arsenates(III) were prepared by adding their sulphate solutions into arsenious solution obtained by dissolving As2O3 in NaOH aqueous solution. The structure and crystal lattice of the products and amount of the elements in precipitations were characterized by X-ray diffraction(XRD) and Atomic Absorption Spectrometry(AAS), respectively. Based on the results of XRD in the conditions of NaOH concentration = 1 mol/L, n(OH)/n(As) = 1:1, n(Cu)/n(As) = 1:2, reaction temperature 90°C and reaction time 8h, a mono-phase crystalline copper arsenate(III) with the chemical composition of Cu(AsO2)2 and tetragonal crystal lattice was synthesized. In these conditions, the yields of arsenic and copper precipitation from the solution were 93.81% and 97.68%, respectively. Based on the XRD results in the conditions of NaOH concentration = 1 L, n(OH)/n(As) = 1:1, n(Zn)/n(As) = 1:2, reaction temperature 80°C, reaction time 2h and washing pH = 6, a mono-phase crystalline zinc arsenate (III) with the chemical composition of Zn(AsO2)2 and monoclinic crystal lattice was synthesized. In these conditions, the yields of arsenic and zinc extraction from the solution were 77.70% and 46.37%, respectively.
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Authors and Affiliations

B. Behnajady
1
ORCID: ORCID
J. Moghaddam
2
ORCID: ORCID

  1. Sahand University of Technology, Materials Engineering Facult y, Advanced Material Research Centre, Tabriz 1996-51335, Iran
  2. University of Zanjan, Materials and Metallurgical Engineering Department, Zanjan 38791-45371, Iran
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Abstract

In order to improve the properties of the materials produced by the powder metallurgy method, first of all, powders (16.59% AlN + 6.63% WC) were coated with nickel (Ni) by electroless method, and then box boriding, which is one of the most widely used surface coating methods, was applied. A composite formed with (16.59% AlN + 6.63% WC)76.7Ni was prepared under the Ar shroud in the temperature range of 1000-1400°C. Pulse-echo technique was used for ultrasonic velocity measurements on Ni coated (16.59% AlN + 6.63% WC) samples. It is aimed to examine the change of physical, mechanical and ultrasonic properties of the obtained ceramic-metal composites depending on different sintering temperatures. In addition, the samples were characterized by mechanical and metallographic examination. The results show that the longitudinal and transverse ultrasonic velocity values and ultrasonic modulus (shear, bulk, Young’s etc.) values increase simultaneously with the increase of sintering temperature. The highest microhardness value was observed in composite samples sintered at 1400°C and its value was 1150.80 Hv. The increased strength is mainly due to grain refinement and strong interfacial bonding between Ni particles and AlN and WC matrix.
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Authors and Affiliations

V. Özkan Bilici
1
ORCID: ORCID
A. Yönetken
2
ORCID: ORCID
A. Erol
3
ORCID: ORCID

  1. Afyon Kocatepe University, Science And Literature Faculty, Physics Dept., 03200, Afyonkarahisar, Turkey
  2. Afyon Kocatepe University, Engineering Faculty, Electrical Engineering Dept., 03200, Afyonkarahisar, Turkey
  3. Afyon Kocatepe University, Technology Faculty, Metallurgy and Materials Engineering Dept., 03200, Afyonkarahisar, Turkey
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Abstract

Geopolymers are commonly recognized as sustainable alternatives to OPC and it has broad range of applications. Certain properties of geopolymer such as density are concerned in order to apply in the construction industry. Different densities of geopolymer could be obtained by varying the concentration of the alkaline activator. However, the densities do not differ much. Hence, a different production method of geopolymer can be applied. This study aimed to investigate the physical properties and compressive strength of pressed and cast fly ash geopolymer. The geopolymer samples were prepared by using pressing and casting method. Geopolymer samples without foam addition and with foam addition were prepared in order to achieve different densities of samples. The results demonstrated that the pressed sample has the highest bulk density (2285 kg/m3) whereas the cast sample with added highest ratio of foam has the lowest bulk density (1293 kg/m3). The apparent porosity and water absorption result were inversely proportional to the bulk density result. The densest geopolymer obtained the highest compressive strength (61 MPa) and the lightest geopolymer obtained the lowest compressive strength (7 MPa).
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Authors and Affiliations

L. Jia-Ni
1 2
ORCID: ORCID
L. Yun-Ming
1 2
ORCID: ORCID
M.M.A.B. Abdullah
1 2
ORCID: ORCID
T. Hoe-Woon
1 3
ORCID: ORCID
H. Yong-Jie
1 2
ORCID: ORCID
O. Shee-Ween
1 2
ORCID: ORCID
O. Wan-En
1 2
ORCID: ORCID

  1. Universiti Malaysia Perlis, Center of Excellence Geopolymer and Green Technology (CeGeoGTech), 01000 Kangar, Perlis, Malaysia
  2. Universiti Malaysia Perlis, 01000 Kangar, Faculty of Chemical Engineering Technology, Perlis, Malaysia
  3. Universiti Malaysia Perlis, Faculty of Mechanical Engineering Technology, 02600 Arau, Perlis, Malaysia
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Abstract

Water-to-binder (W/B) ratio has a great influence on the bulk density, compressive strength and morphology of fly ash/ladle furnace slag (FA/LFS) blended one-part geopolymer. The objective of this work is to evaluate the effect of W/B ratio on the performance of the one-part geopolymer. The one-part geopolymer were prepared at W/B ratio of 0.20-0.30 and cured at room temperature for 28 days. The bulk density, water absorption, apparent porosity and compressive strength were determined, while the morphology was examined by scanning electron microscopy (SEM). The results showed that the one-part geopolymer with W/B ratio of 0.25 had highest compressive strength (39 MPa) with denser (2.1 g/cm3) structure as well as low water absorption (3.97%) and low apparent porosity (8.33%). The micrograph showed the optimal one-part geopolymer has less agglomeration of FA and LFS particles.
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Authors and Affiliations

H. Yong-Jie
1 2
ORCID: ORCID
H. Cheng-Yong
2 3
ORCID: ORCID
M.M.A.B. Abdullah
1 2
ORCID: ORCID
L. Yeng-Seng
4
ORCID: ORCID
O. Shee-Ween
1 2
ORCID: ORCID
O. Wan-En
1 2
ORCID: ORCID
L. Jia-Ni
1 2
ORCID: ORCID
T. Hoe-Woon
2 3
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering Technology, 01000 Kangar, Perlis, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Center of Excellence Geopolymer and Green Technology (CeGeoGTech), 01000 Kangar, Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering Technology, 02600 Arau, Perlis, Malaysia
  4. Universiti Malaysia Perlis (UniMAP), Center of Excellence Advanced Communicat ion Engineering, 01000 Kangar, Perlis, Malaysia
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Abstract

The degradation of the condition of wastewater is becoming more and more serious due to the endless development. One of the main reasons is heavy metal contamination, which causes significant harm to the climate and humanity, such as bad health consequences, environmental degradation, and air pollution. Adsorption, which uses proven adsorbents such as activated carbon, is one of the most common methods for heavy metal removal in wastewater. However, since activated carbon is very expensive to build and repair due to complex production, most people choose another material to overcome this problem. Researchers have recently focused on finding low-cost adsorbents, which are typically industrial, agricultural and food wastes that can generate in large quantities. However, Alkali-Activated Materials (AAMs) have been recognized as a novel possible adsorbent because they are cheap, made from solid aluminosilicate and extremely alkaline activator solution, making them appropriate for usage in the civil engineering specialty. Moreover, they have become an option for various applications due to their unique geopolymer structure, which is highly mechanically, chemically and thermally stable. Hydroxyapatite (HAP) can be extremely useful in this application, as it is a promising biomaterial that has great potential for a low-cost AAMs adsorbent. The purpose of this study is to analyze the present development of a potential economic alternative adsorbent, particularly based on alkali-activated materials (known as geopolymers), for the elimination of heavy metal pollutants in wastewater using adsorption techniques.
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Authors and Affiliations

F.F. Kamarzaman
1 2
ORCID: ORCID
M.M. Al Bakri Abdullah
1 2
ORCID: ORCID
M.R. Rozainy
3
R. Ahmad
1
ORCID: ORCID
W.M.W. Ibrahim
1
ORCID: ORCID
M.F. Omar
2
ORCID: ORCID
C.M.R. Ghazali
4
ORCID: ORCID
W.M.A.W. Ibrahim
2

  1. Universiti Malaysia Perlis, Center of Excellence Geopolymer and Green Technology (CEGeoGTech), 01000 Perlis, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering Technology, 01000 Perlis, Malaysia
  3. Universiti Sains Malaysia, School of Civil Engineering, Engineering Campus, 14300, Pulau Pinang, Malaysia
  4. Universiti Malaysia Terengganu, Faculty of Ocean Engineering Technology and Informatic, 21030 Terengganu, Malaysia
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Abstract

This paper is designed to investigate the wear and mechanical characterization of metal matrix composites (MMCs) by using micro and nano SiC on Al to study the influence of micro/nano SiC on the properties of fabiricated composite. Micro and nano-composites with 1-4% of SiCp were developed using stircasting processes. From the outcomes, an improved grain refinement of micro and nano-composites when compared to monolithic was seen from the microstructural study. It found that an increase in SiC particulates content caused enhanced mechanical properties. Though, nano SiC reinforced MMCs resulted in improved mechanical properties compared to micro sized SiC particulates reinforced MMCs. The wear study was evaluated for comparison of micro/nano MMCs. The investigation indicates that, wear resistance of nano composites is better as compared to micro-SiCp reinforced MMCs. Fractured surfaces were inspected by the SEM analysis to study the nature of fracture in the micro and nano composite samples.
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Authors and Affiliations

M. Ravikumar
1
ORCID: ORCID
H.N. Reddappa
2
ORCID: ORCID
R. Suresh
3
ORCID: ORCID
E.R. Babu
2
ORCID: ORCID
C. Reddy Nagaraja
2
ORCID: ORCID

  1. B.M.S College of Engineering, Department of Mechanical Engineering, Bangalore, Karnataka, India
  2. Bangalore Institute of Technology, Departm ent of Mechanical Engineering, Bangalore, Karnataka, India
  3. M.S. Ramaiah University of Applied Sciences, Departm ent of Mechanical and Manufacturing Engineering, Bangalore-560058, Karnataka, India
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Abstract

Some efforts have proposed the utilization of Sidoarjo mud for geopolymer paste. However, the original dry mud in geopolymer concrete showed decreased compressive strength and increased required water. In this paper, the one-part method is proposed to reduce the water in the mixture. First, the mud was chemically flocculated. Then, the dry mud was mixed with fly ash, activated geothermal silicate, and sodium hydroxide mixture in solid form before then the distilled water was added. This reduced the required water to 50% compared to the two-part method. The flocculant sedimented heavy metal that resulted in higher compressive strength at a later age. At 28 days, dry flocculated mud showed higher compressive strength than the original dry mud, with a compressive strength of 13 MPa and 11 MPa, respectively. This is because of the increase of silica, alumina, and iron content from 70% in dry LUSI to 75% in dry flocculated mud.
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Authors and Affiliations

T. Syihabuddin
1
ORCID: ORCID
J.J. Ekaputri
1
ORCID: ORCID
M.A. Maulana
1
ORCID: ORCID
R.A.A. Soemitro
1
ORCID: ORCID
H.T.B.M. Pet rus
2
ORCID: ORCID
F. Chikako
3
ORCID: ORCID

  1. Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
  2. Universitas Gadjah Mada, Sleman, Indonesia
  3. Yokohama National University, Yokohama, Japan
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Abstract

The use of lightweight aggregate can bring advantages to the construction field. Lightweight aggregate has been used due to its lower density and can reduce the dead load applied to the structural elements. Due to the number of natural resources, such as natural aggregate having decreased, producing lightweight aggregate from industrial waste materials can overcome the problem. Different methods produce lightweight aggregates, such as sintering, cold bonding, and autoclaving. From earlier studies, spherical sintered lightweight aggregate can manufacture structural concrete. Using artificial lightweight aggregate in concrete can achieve the minimum strength requirement of structural concrete and has been applied in the construction field. The properties of lightweight aggregate, such as specific gravity, water absorption, crushing strength, and impact value, are reviewed. Besides that, the mechanical and thermal properties review is also important for using lightweight aggregate in concrete. The review also indicates that aggregate produced using the cold bonding method and autoclaving method potential can be used in the concrete.
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Authors and Affiliations

D.L. Chuan Hao
1 2
ORCID: ORCID
R.A. Razak
1 2
ORCID: ORCID
Z. Yahya
1 3
ORCID: ORCID
M.M. Al Bakri Abdullah
2 4
ORCID: ORCID
A. Abdullah
2 5
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Faculty of Civil Engineering & Technology, Perlis, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Geopolymer & Green Technology, Centre of Excellence (CEGeoGTech), Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Geopolym er & Green Technology, Centre of Excellence (CEGeoGTech), Perlis, Malaysia
  4. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering & Technology, Perlis, Malaysia
  5. Universiti Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering & Technology, Perlis, Malaysia
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Abstract

Alkali activation for producing alkali-activated materials is noted as a complex due to involving several reactions. Due to complexity of the reactions, various techniques have been applied by past researches on monitoring the evolution of alkali-activated materials. The evolution monitored during alkali activation include internal relative humidity, structural evolution, ultrasonic evolution and heat evolution. All of these techniques provide real-time information which is significant for evaluating the reaction process of alkali activation with respected parameters applied thus will be briefly reviewed in this paper. In addition, among those techniques, due to its reliability, heat evolution is one noted as one of the most common techniques applied to elucidate the alkali activation process. Therefore, the potential of heat evolution will also be significantly highlighted in this study.
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Authors and Affiliations

R. Mohamed
1 2
ORCID: ORCID
R.A. Razak
1 3
ORCID: ORCID
M.M. Al Bakri Abdullah
1 2
ORCID: ORCID
S.Z. Abd Rahim
1
ORCID: ORCID
B. Kim
4
ORCID: ORCID
T. Imjai
5
ORCID: ORCID
I.H. Aziz
1
ORCID: ORCID
D.L.Ch. Hao
1 3
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Geopolymer & Green Technology, Centre of Excellence (CEGeoGTech), Perlis, Malaysia
  2. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering Technology Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Faculty of Civil Engineering Technology, Perlis, Malaysia
  4. University of Plymouth, School of Engineering, Computing and Mathematics, Plymouth PL4 8AA, United Kingdom
  5. School of Engineering and Technology, Walailak University, Nakhorn Si Thammarat, 80160, Thailand
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Abstract

Electroless deposition is a method of metallizing parts without needing for an electrical source that can be performed on electrically conductive and non-conductive materials. Adhesion quality is an essential aspect of the electroless deposition process that determines the metal deposition conditions. The properties of stereolithography (SLA) 3D printed parts can be improved through the metallization process for various applications. In this study, optimization through the orthogonal design method was used to obtain the optimal processing parameters of electroless copper deposition on desktop SLA material with respect to adhesion quality. Experimental work was carried out according to the L9 (34) orthogonal array, followed by an evaluation of the signal-to-noise (S/N) ratio and analysis of variance (ANOVA). Based on the S/N ratio results, the optimal processing parameters for adhesion quality were potassium hydroxide concentration (400 g/L), etching time (30 min), formaldehyde concentration (3.75 mL/L) and deposition time (30 min). The results of the study are useful for industries such as rapid tooling, rapid prototyping, and semiconductors.
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Authors and Affiliations

A. Ahmad
1 2
ORCID: ORCID
Md Saidin Wahab
3
ORCID: ORCID
K. Kamarudin
1 2
ORCID: ORCID
H. Hehsan
1 2
ORCID: ORCID

  1. Universiti Tun Hussein Onn Malaysia, Facult y of Engineering Technology, Department of Mechanical Engineering Technology, Pagoh Edu Hub, KM 1, Jalan Panchor, 84600 Pagoh, Johor, Malaysia
  2. Universiti Tun Hussein Onn Malaysia, Innovative Manufacturing Technology (IMT), Facult y of Engineering Technology, Pagoh Edu Hub, KM 1, Jalan Panchor, 84600 Pagoh, Johor, Malaysia
  3. Universiti Tun Hussein Onn Malaysia, Adva nced Manufact uring and Mat erials Centre (AMMC), Parit Raja, 86400 Bat u Pahat , Johor, Malaysia
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Abstract

The presence of nickel ions in wastewater is a significant environmental concern due to its toxicity, which can cause severe health problems. Metakaolin is a pozzolanic material that can be activated by alkali to produce a highly porous and reactive material that can be utilised as a heavy metal ion adsorbent. However, the adsorption capacity of metakaolin-based adsorbents is limited by their surface chemistry and porosity. Metakaolin-based alkali-activated materials adsorbent modified with hydrogen peroxide can effectively remove nickel ions from wastewater. The modification process increases the surface area and porosity of the adsorbent, enhancing its adsorption capacity. The modified adsorbent (1.00 wt.% H2O2) showed a higher sorption capacity of 26.57 mg/g and efficiency of 85.22% compared to the non-modified adsorbent (10.55 mg/g) sorption capacity and 45.63% nickel removal efficiency, indicating the potential of hydrogen peroxide-modified adsorbents as an economical and ecologically sustainable solution for environmental applications, particularly for metal immobilization.
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Authors and Affiliations

M. Ibrahim
1 2
ORCID: ORCID
W.M. Wan Ibrahim
2 3
ORCID: ORCID
M.M. Al Bakri Abdullah
1 2
ORCID: ORCID
A.S. Sauffi
1 2
ORCID: ORCID
R. Ahmad
2 3
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical Engineering & Technology, Kompleks Pusat Pengajian Jejawi 3, 02600, Arau, Perlis, Malaysia
  2. Universiti Malaysia Perlis, Center of Excellence Geopolymer and Green Technology (CEGeoGTech), 01000, Kangar, Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering & Technology, 02600, Arau, Perlis, Malaysia
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Abstract

Circulating fluidized bed combustion (CFBC) fly ash has the potential as a precursor to making geopolymer concrete because of its rich silica and alumina content. However, there is a problem in utilizing CFBC fly ash caused by its chemical and physical properties that differ from the widely used pulverized coal combustion (PCC) fly ash. CFBC fly ash has a higher water requirement than PCC fly ash due to its angular particle shape, and higher sulfur and lime contained also caused a different reaction in the geopolymer system. Mechanical activation by milling the CFBC fly ash could decrease the water requirement in the mixture and make good quality CFBC fly sh-based geopolymer concrete. Three CFBC fly ash samples from different power plants in Indonesia with different chemical compositions were used in this research. The first had a low lime and no sulfur content, the second had high lime and no sulfur content, and the third had high lime and sulfur content. The milling process using a ball mill for two hours decreased the water requirement, as shown in the lower normal consistency of the fly ash. The reactivity also was increased, shown by the faster initial setting time. Besides its higher reactivity, lower water requirement increased the compressive strength of geopolymer mortar produced. This study also showed that the existence of calcium and sulfur content in the CFBC fly ash could cause unexpected results shown by the change of initial setting time, water requirement, and compressive strength.
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Authors and Affiliations

A. Antoni
1
ORCID: ORCID
I.J. Yugiarto
1
ORCID: ORCID
R.J.S. Hadi
1
ORCID: ORCID
A. Kuncoro
1
ORCID: ORCID
D. Hardjito
1
ORCID: ORCID

  1. Petra Christian University, Department of Civil Engineering, Jl. Siwalankerto 121-131, Surabaya 60236, Indonesia
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Abstract

This paper presents the morphology of the metakaolin/dolomite geopolymer after being exposed to high temperature and compare the findings with the morphology that has not been exposed to the temperature. The geopolymers were exposed at temperatures from 200°C up to 800°C. The geopolymer was a constant mix of 90% metakaolin and 10% dolomite with 10 NaOH molarity, 0.8 solid to liquid ratio, and 2.0 by mass of alkaline activator. The morphology of geopolymer exposed to high temperature contains many pores and as the temperature rises, the pores become huge, and a higher quantity of pores can be observed. The surface analysis, compressive strength, and water absorption test were also done to support the findings. The compressive strength calculation was based on weight loss. The lowest compressive strength loss was at 200°C temperature exposure with 10.98%. Meanwhile, the highest compressive strength loss was at 800°C temperature exposure with 48.54%. In comparison, this metakaolin/dolomite geopolymer archive better properties compared to the concrete and metakaolin past studies.
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Authors and Affiliations

A.S. Sauffi
ORCID: ORCID
W.M. Wan Ibrahim
ORCID: ORCID
M.M. Al Bakri Abdullah
ORCID: ORCID
M. Ibrahim
ORCID: ORCID
R. Ahmad
ORCID: ORCID
F.A. Zaidi
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Abstract

Geopolymer concrete is a new sustainable and environmentally friendly composite with great potential to replace conventional concrete that is mostly produced by ordinary Portland cement (OPC). Binders used for geopolymer concrete such as fly ash and blast furnaces are mostly industrial wastes or by -products containing high silica and aluminium content that act as stimulants for geopolymerization. Furthermore, geopolymers also exhibit better durability and corrosion resistance than OPCs. However, material subjected to underwater placement method typically exhibit a decrease in properties. While geopolymer has not been widely used as underwater concreting material, this research is purposed to identify the effect of underwater placement method towards geopolymer in terms of microstructure analysis. Using different molarities of sodium hydroxide (NaOH), the optimum compressive strength will be discussed for underwater concrete while correlating with the microstructure result. For alkaline activators, the ratio used is 2.5 and the ratio for solid to liquid is 2.5. The molarities used for alkaline activators were 8 M, 10 M and 12 M. Using the tremie method for underwater concrete, it is possible to measure the leaching loss with respect to the objective of this research. The best compressive strength result is 12 M. The SEM result support with 12 M molarity had less cavities and lowest density.
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Authors and Affiliations

F.H.A. Zaidi
1 2
ORCID: ORCID
A. Romisuhani
1 3
ORCID: ORCID
M.M.A.B. Abdullah
1 2
ORCID: ORCID
W.M.W. Ibrahim
1 3
ORCID: ORCID
M.I.A. Bistamam
1
A.S. Sauffi
1
ORCID: ORCID
L.Y. Li
4
ORCID: ORCID

  1. Universiti Malaysia Perlis (UniMAP), Faculty of Chemical and Engineering Technology, 01000 Perlis,Center of Excellence Geopolymer and Green Technology (CEGeoGTech), Malaysia
  2. Universiti Malaysia Perlis, Faculty of Chemical Engineering and Technology, 02600 Jejaw i, Arau, Perlis, Malaysia
  3. Universiti Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering and Technology, 01000 Perlis, Malaysia
  4. University of Plymouth, School of Engineering, Plymouth PL4 8AA, United Kingdom
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Abstract

The corrosion inhibition performance of clindamycin for mild steel in 2.0 M H2SO4 has been studied using gravimetric and electrochemical methods. The results showed that the clindamycin inhibited mild steel corrosion in 2.0 M H2SO4 solution. The inhibition efficiency was found to increase with an increase in the concentration of clindamycin and decrease with an increase in the temperature. The maximum inhibition efficiency was obtained at 303 K (91.1%). Potentiodynamic polarization results reveal that clindamycin is a cathodic-type corrosion inhibitor lower concentrations and an anodic-type corrosion inhibitor at higher concentrations. The experimental data fitted the Langmuir adsorption isotherm and the adsorption of clindamycin was found to be spontaneous. The values of activation energy and Gibb’s free energy were found within the range of limits expected for the mechanism of physical adsorption.
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Authors and Affiliations

A.A. Bamigbola
1
ORCID: ORCID
A.I. Ikeuba
2
ORCID: ORCID
C.E. Gimba
1
ORCID: ORCID
M.E. Ikpi
3
ORCID: ORCID
O.S. Olajire
4
ORCID: ORCID
F.E. Umo
3
ORCID: ORCID

  1. Ahmadu Bello University Zaria, Department of Chemistry, Zaria, Nigeria
  2. University of Calabar, Materials Chemistry Research Group, Department of Pure and Applied Chemistry, Calabar, Nigeria
  3. University of Calabar, Department of Pure and Applied Chemistry, Calabar, Nigeria
  4. Mountain Top University, Department of Chemical Sciences, Ibafo, Ogun State, Nigeria
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Abstract

Composite materials are synthesized by using natural cellulose fibers with matrix, due to their improved properties. In this work, banana and palm fibers are treated with 2% and 8% NaoH, respectively, for the removal of lignin and hemicelluloses. The hybrid composite was fabricated by using epoxy resin as the matrix and both the fibers as reinforcement through the hand lay-up method. By varying the banana and palm fibers in the range of 5-15% wt. and 7.5-22.5% wt. in the composite of 20% wt. and 30% wt. reinforcement, respectively, The composite consists of 5/15% wt. treated fibers, having more influence on compressive strength of 222.46 MPa and flexural strength of 535 MPa. However, 7.5/22.5% wt. treated composite has a higher impact resistance of 14.6 J and 10/10% treated composite gained a higher water absorption percentage weight of 1.16% at 216 hours. From the experiment, the composite with 5/15% wt. fibers of 20% wt. reinforcement and 80% wt. epoxy is suitable for making kitchen slabs.
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Authors and Affiliations

B. Selvam
1
G.M. Balamurugan
2
ORCID: ORCID
B. Gebrehiwot
3

  1. M.I.E.T. Engineering College, Department of Mechanical Engineering, Thiruchirappali, Tamilnadu, India
  2. Dhanalakshmi Srinivasan University, Department of Mechanical Engineering, Tiruchirappalli, Tamilnadu, India
  3. Mekelle University, School of Mechanical and Industrial Engineering, Tigray, Ethiopia
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Abstract

This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives – niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-β-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy.
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Authors and Affiliations

G. Dercz
1
ORCID: ORCID
I. Matuła
1
ORCID: ORCID
K. Prusik
1
ORCID: ORCID
J. Zając
1
M. Szklarska
1
ORCID: ORCID
A. Kazek-Kęsik
2
ORCID: ORCID
W. Simka
2
ORCID: ORCID

  1. University of Silesia in Katowice, Institute of Materials Engineering, 75 Pułku Piechoty Str. 1A, 41-500 Chorzów, Poland
  2. Silesian University of Technology, Faculty of Chemistry, B. Krzywoustego Str. 6, 44-100 Gliwice, Poland
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Abstract

The microstructure evolution, texture and tensile properties of the Mg-8Li dual-phase alloys processed by hot-extrusion and friction stir processing were investigated. It was found that the friction stir processing was more advantageous when compared with hot-extrusion in achieving the superior mechanical properties. The tensile strength, yield strength and elongation of the as-FSPed alloy reached 235.4 MPa, 185.3 MPa and 35.6%, respectively. The outstanding strength-ductility combination of the ­as-FSPed Mg-8Li alloy was ascribed to refined grains, weakened texture and formation of high-fraction high angle grain boundaries.
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Authors and Affiliations

Li Zhang
1
ORCID: ORCID
Nan Li
1
ORCID: ORCID

  1. Shenyang Aerospace University, Shenyang, School of Materials Science and Engineering, China
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Abstract

In this study, blast furnace dust and iron concentrate were used as raw materials and graphite as reducing agent for mixed compacts. The briquettes were roasted in a high temperature tube furnace at 1200°C and kept for a certain time to simulate the pre-reduction sintering dezincification process. The reduced briquettes were characterized by X-ray diffraction, scanning electron microscopy, Energy Dispersive Spectroscopy and flame atomic absorption spectrometry. The effects of C/O molar ratio, basicity and pre-reduction time on the zinc removal rate and pre-reduction degree of the pre-reduction sintered products were studied, and the removal mechanism of zinc was further investigated. The results show that the pre-reduction sintering process can effectively achieve the zinc volatility removal while meeting the requirements of subsequent blast furnace production. The zinc removal rate of pre-reduced sintered products increased with the prolongation of pre-reduction time, increased first and then decreased with the increase of C/O molar ratio and basicity. The pre-reduction degree and Zn removal rate showed the same variation pattern. When the briquettes with C/O molar ratio of 1.0 and basicity of 1.9 were reduced for 20 min, the zinc removal rate and pre-reduction degree could reach 90.40% and 87.74%, respectively, indicating that a large amount of zinc was removed and most of the metallic iron had been reduced. The research results can provide some theoretical basis for industrial production.
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Authors and Affiliations

J. Ju
1 2
ORCID: ORCID
R. Li
1 2
ORCID: ORCID
X. Xing
1 2
ORCID: ORCID
X. Jiang