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In Search of Magnetic Properties of Samarium Cobalt (Sm2Co17) within a Low-Temperature Sintering Process Poppy Puspitasari; A. Muhammad; A. A. Permanasari; T. Pasang; S. M. S. N. S. Zahari; N. A. Ahmad
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 3 Year 2021 (September 2021)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.3.10482.517-524

Abstract

Samarium cobalt is known as super high density magnetic material with large magnetic anisotropy energy. Samarium–cobalt exhibits manipulative magnetic properties as a rare-earth material which has different properties in a low sintering temperature. It is therefore of paramount importance to investigate samarium cobalt (Sm2Co17) magnetic properties in the low temperature sintering condition. Sm2Co17, which is utilized in this research, is synthesized via the sol–gel process at sintering temperatures of 400, 500, and 600 °C. Subsequently, the crystallites indicate the formation of a single-phase Sm2Co17 on all the samples in all temperature variations. Moreover, the peaks in the X-ray diffraction analysis of crystallite sizes calculated using the Scherrer equation are 17.730, 15.197, and 13.296 nm at 400, 500, and 600 °C. Through scanning electron microscopy, the particles are found to be relatively large and agglomerated, with average sizes of 143.65, 168.78, and 237.26 nm. The functional groups are also analyzed via Fourier-transform infrared spectroscopy, which results in the appearance of several bonds in the samples, for example, alkyl halides, alkanes, and esters with aromatic functional groups on the fingerprint area and alkynes, alkyl halides, and alcohol functional groups at a wavelength of above 1500 cm. The test results of the magnetic properties using vibrating-sample magnetometer (VSM) revealed high coercivity and retentivity in the samples sintered at 400 °C. However, the highest saturation occurs in the samples sintered at 600 ℃. At a low sintering temperature (below 1000 °C), samarium cobalt shows as the soft magnetic material. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Tribology Properties on 5W-30 Synthetic Oil with Surfactant and Nanomaterial Oxide Addition Puspitasari, Poppy; Permanasari, Avita Ayu; Warestu, Ayu; Arifiansyah, Gilang Putra Pratama; Pramono, Diki Dwi; Pasang, Timotius
Automotive Experiences Vol 6 No 3 (2023)
Publisher : Automotive Laboratory of Universitas Muhammadiyah Magelang in collaboration with Association of Indonesian Vocational Educators (AIVE)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/ae.10115

Abstract

This study analyzes the tribological properties of 5W-30 synthetic oil with the addition of surfactants and oxide nanomaterials. This research used SAE 5W-30 lubricant base material with the addition of Aluminum Oxide (Al2O3), Titanium Dioxide (TiO2), and Hybrid Aluminum Oxide (Al2O3) - Titanium Dioxide (TiO2) nanomaterials. The nano lubricants were synthesized using a two-step method by adding nanomaterials by 0.05% volume fraction, followed by 50 ml of 5W-30 synthetic oil and polyvinylpyrrolidone (PVP) surfactant by 0.1%. Then, it was stirred using a magnetic stirrer for 20 minutes, followed by an ultrasonic homogenizer process for 30 minutes. Further, the nanolubricant was tested to identify its thermophysical properties, including density, dynamic viscosity, and sedimentation. It also underwent tribological testing, including wear, coefficient of friction, and surface roughness. Further, the nanomaterial was characterized using SEM, XRD, and FTIR. The morphological analysis using SEM suggested an irregular shape of the Al2O3 nanomaterial surface, while TiO2 has a spherical shape. Besides, phase identification with XRD testing showed corundum and anatase phases. Functional group analysis through the FTIR showedthe presence of Ti-O and Al-O. The highest density and viscosity results without surfactants were obtained in hybrid nanolubricant 779 kg/mm3 and 0.0579 Pa.s, while the use of surfactants resulted in 788.89 kg/mm3 of density and 0.0695 Pa.sviscosity. Tribological gray cast iron FC25 results in the best COF value observed in SAE 5W-30 + PVP-TiO2 lubrication (0.093). The lowest wear mass without surfactant was obtained in the Al2O3-TiO2 nanolubricant hybrid (0.02 grams), the lowest surface roughness in a mixture of PVP and TiO2 surfactants was 0.743 μm. Meanwhile, the surface morphology of gray cast iron FC25 with hybrid nanolubricant SAE 5W-30 (Al2O3-TiO2) and Nanolubricant SAE 5W-30+ (PVP-TiO2) produced the smoothest surface.
Development of interactive media sheet metal design modeling based on software Autodesk Inventor Professional 2023 Adi Pangestu, Deni Kusuma; Widiyanti, Widiyanti; Suyetno, Agus; Puspitasari, Poppy
Jurnal Inovasi Teknologi Pendidikan Vol. 11 No. 3 (2024): September
Publisher : Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jitp.v11i3.72805

Abstract

This research and development aims to produce learning media products presented interactively and practically based on Autodesk Inventor Professional 2023 student version software and analyze the feasibility level of learning media for CAD Manufacturing Drawing Techniques subjects to improve competence in the field of machining techniques at  Vocational High School 1 Kediri. The type of research used is research and development (R&D) using the Borg and Gall model, It involved 6 students for the small-scale testing and 32 students for the large-scale testing. Based on the data obtained and descriptive analysis, among others, the results of media expert validation were 98.44%, material expert validation was 89.28%, small-scale trials were 92.08%, and operational trial results were 91.09%. These results indicate that the interactive learning media product sheet metal design modeling meets the criteria very well and can be utilized as a learning tool.
Synthesis and Applications of Hematite α-Fe2O3 : a Review Muhajir, Muhamad; Puspitasari, Poppy; Abdul Razak, Jeefferie
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 3, No 2 (2019)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (739.115 KB) | DOI: 10.17977/um016v3i22019p051

Abstract

This article reviewed the hematite α-Fe2O3, which focuses on its material properties, nanostructures, synthesis techniques, and its numerous applications. Researchers prepared the hematite nanostructure using the synthesis methods, such as hydrothermal, and, further, enhanced it by improving the techniques to accommodate the best performance for specific applications and to explore new applications of hematite in humidity sensing.
Effect of Heating Temperature, Holding Time and Stabilization Temperature on the Al-Foam Properties Puspitasari, Dewi; Puspitasari, Poppy; Mustapha, Mazli; Ginta, Turnad Lenggo
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 7, No 2 (2023)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v7i22023p147

Abstract

The interest in metallic foam is increasing since their cellular structures have a unique combination of properties such as high stiffness, low density, lightweight, high specific strength, and thermal insulation. Commonly, the performance of metallic foam can be improved by the heat treatment process. However, the previous heat treatment methods still present the brittle crack path and the research on heat treatments of the metal foam properties is very limited. In this study, individual parameters in stress relieving treatment that contribute to Al-Foam properties were investigated. The stress-relieving process of the samples was performed using a vacuum furnace. The composition of aluminium foam was determined by X-Ray Fluorescence (XRF). The hardness test was conducted using a microhardness tester. Quasi-static compression test was conducted by a universal testing machine. From the SEM-EDX elemental images, it can be observed that traces of Ca, Fe, Ti, and Si have a homogeneous distribution in the Al-matrix. In the result obtained, the mechanical properties of aluminium alloy foam decrease when the heating temperature is enhanced. The mechanical properties of closed-cell aluminium alloy increase with the reduction of the holding temperature. This was due to the recovery and recrystallization process which depended on time and temperature during the heat treatment process. The mechanical properties of aluminium foam were raised after increasing the stabilization temperature. This finding was due to the vibrational atomic motion in the recovery process.
Performance Enhancement of Shell and Tube Heat Exchanger on Parallel Flow with Single Segmental Baffle Permanasari, Avita Ayu; Puspitasari, Poppy; Sukarni, Sukarni; Wulandari, Retno
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 4, No 1 (2020)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v4i12020p043

Abstract

The shell and tube heat exchanger was a tool to exchange the heat energy between fluids with different temperatures that occurred through direct or indirect contact. The energy exchange in fluids could be occurred with the same phase (liquid to liquid or gas to gas) or two fluids with different phase. To date, the process of heat transfer in the industrial field was crucial in machine work. Therefore, there were studies directed to optimize and develop the function and thermal performance of a heat exchanger by adding Baffles to the side of the shell. Vortex flow that occurs with the addition of baffles will make the area of fluid contact in the shell with the tube wall larger, so the heat transfer between the two fluids will increase. This study aimed to obtain the efficiency of the heat exchanger and its effectiveness when put on parallel flow. The heat exchanger had the dimensions of 54.6 x 10-3 m in outer diameter and 22.4 x 10-3 m in inner diameter with a tube thickness of 3 mm. The variations on water flow from both fluids were 0.5, 1, 1.5, 2 l/min for hot water and 1, 2, 3, 4 l/min for cold water to obtain the effectiveness of heat exchanger on parallel flow. This research heated the hot fluid in electric heating and used water as the cold fluid. The results showed that heat exchanger with single segmental baffle was more efficient in reducing heat in hot water than heat exchanger without bafe. The flow of fluid affected the average temperature difference; the higher the flow of fluid created a more significant temperature difference. The use of single segmental baffle affected the average temperature difference that was higher than without the baffle. The use of single segmental baffle also influenced the heat transfer greater than without baffle because of the longer distance travelled by the fluid on single segmental baffle with the same flow. Thus, the heat transfer process that occurred was more significant by using a single segmental baffle.
Synthesis and Characterization of Nitrogen-Doped Activated Carbon for Lithium Battery Anode Applications Trihutomo, Prihanto; Puspitasari, Poppy; Radja, Muhammad Bustomi; Busono, Milzam Rahmat
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 7, No 1 (2023)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v7i12023p020

Abstract

Nitrogen-dopped activated carbon was synthesized to see its effect on the characterization of the nitrogen surface functional groups, crystal size, and morphology of the resulting sample. Synthesis of nitrogen-doped activated carbon was carried out by varying the addition of Urea as a nitrogen doping source. Activated carbon compared its characteristics with variations in the concentration of added Urea to activated carbon, at 1:3 and 1:5. The FTIR results obtained were the presence of functional groups indicating the presence of nitrogen bonds in each sample. The crystallinity results showed that the samples were classified as crystalline and nitrogen doping influenced the size of the crystallinity of each sample. The morphology of nitrogen-doped activated carbon shows differences in the grain size of nitrogen-doped activated carbon. Crystallinity and morphology have been shown to affect battery anode performance. The more crystalline of anode material, the electrochemical properties are better. The smaller the grain size of the sample morphology, the stability of the battery cycle is to be great.    
Investigate the Potential Renewable Energy of Microalgae Spirulina sp Using Proximate Analyzer, SEM-EDX, and Thermogravimetry Zakaria, Yahya; Sukarni, Sukarni; Puspitasari, Poppy; Mufti, Nandang; Anis, Samsudin; Johari, Anwar
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 6, No 2 (2022)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v6i22022p066

Abstract

Microalgae Spirulina sp which has been cultivated by the Brackishwater Aquaculture Development Center, Situbondo Indonesia were tested for their potential energy performance using proximate analyzer, SEM-EDX, and thermogravimetry. The proximate analyzer showed volatile matter (VM), fixed carbon (FC), moisture, ash content (AC), total sulfur of microalgae Spirulina sp 68.15, 12.57, 11.22, 8.06, and 0.67 (wt%, ar), respectively, and the gross calorific value (GCV) is 4971 kcal/kg (dry basis). SEM-EDX test showed the morphology and chemical content of Spirulina sp. The content of microalgae Spirulina sp is dominated by carbon (C) and oxygen (O), then followed by chlorine (Cl), sodium (Na), potassium (K), sulfur (S), magnesium (Mg), and phosphorus (P). Thermogravimetry pyrolysis test of microalgae Spirulina sp resulted thermogravimetry (TG) analysis and derivative thermogravimetry (DTG) analysis curve, which is divided into three different steps. The moisture of microalga Spirulina sp was vaporized at the first step, started at 27°C, and finished at 173°C with a decomposed mass of about 13.81% of the total initial mass. The second step began at the end of vaporize moisture at about 173°C and ended at around 618 °C. The gasification process occurred in volatile matter content and resulted mass loss of about 57.9% of Spirulina sp total mass. The last step showed the process of gasification of residual substances, started at the end of the volatile matter step, 618°C, and stopped at 995°C with a decomposed mass of 24.6% from total mass.
Comparative Analysis of the Effect Dual Spark Ignition and Single Spark Ignition on Performance and Exhaust Emissions in Bioethanol-Fueled Engines Permanasari, Avita Ayu; Wahidin, Ahmad Faizal; Ismail, Hasan; Komara, Erwin; Puspitasari, Poppy; Lorenzo, Gina A.
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 8, No 1 (2024)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um016v8i12024p123

Abstract

Bioethanol is an alternative fuel that has a high octane value of around 100 to 110, making it difficult to be applied to spark ignition engines directly. So, it is necessary to make adjustments, including increasing combustion efficiency and thermal efficiency of the combustion chamber by increasing the compression ratio and adjusting the ignition system, both in single spark ignition (SSI) and dual spark ignition (DSI) types. The study aims to determine the effect of SSI and DSI applications on engine performance, specific fuel consumption (SFC), and exhaust emissions using 96% and 99% levels of bioethanol fuel. The results showed that, in general, there was an increase in power, torque, and thermal efficiency as well as a decrease in emissions and better SFC in the DSI engine compared to the SSI engine with 99% bioethanol fuel. The highest power was obtained at 6.89 HP or 5.6% higher than the SSI engine, and peak torque was obtained by 14.95 N.m at 6500 rpm on the DSI engine using 99% bioethanol. Meanwhile, the minimum SFC reduction was obtained at 13.87% lower than that of DSI. The highest thermal efficiency of the DSI engine occurs at 7000 rpm, which is 38.19% when using 96% bioethanol. NOx emission increased when using 99% bioethanol on the DSI engine by 15.58% compared to the SSI engine. CO emissions decreased by 72.51% in the DSI engine with 96% bioethanol fuel. At the same time, CO2 experienced the highest decrease of 76.92% at 5500 rpm on 99% bioethanol DSI engine.
Critical Solid Fraction Point Analysis: Case Study on Cement Mill Machine Diaphragm Achyarsyah, Mochamad; Puspitasari, Poppy
Journal of Mechanical Engineering Science and Technology (JMEST) Vol 3, No 2 (2019)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (507.943 KB) | DOI: 10.17977/um016v3i22019p081

Abstract

During the solidification process, metal liquids turn into solid geometry units including the riser and gating system. The disruption in the liquid flow often causes shrinkage in the object. Critical Solid Fraction Point is a critical point where the continuous liquid supply turned solid and unable to pour to some sections. Simulation software can predict the critical solid fraction time of an object and the liquid supply behavior. The simulation helps the designer in the casting design. The application of low steel alloys in the cement industry, e.g., the Diaphragm, needs development to minimize the shrinkage. This research aimed to analyze the critical solid fraction point in the diaphragm steel casting products. The primary objective of this research was to predict the critical solid fraction point during solidification, started from the longest time in the riser/feeder using SOLIDCast 8.1.1 casting software and provided improvement recommendation to minimize the shrinkage.
Co-Authors A. A. Permanasari Abdul Razak, Jeefferie Abdullah, Muhammad Ilman Hakimi Chua Achyarsyah, Mochamad Adi Pangestu, Deni kusuma Afif Achsanul Choiri Agus Setiawan Agus Suyetno Ahmad Atif Fikri Ahmad Munjin Nasih Akbar, Muhamad Rizky Al-Irsyad , Muhammad Alief Muhammad Amat Mukhadis Aminnudin, Aminnudin Amir Hamzah Andika Bagus Nur Rahma Putra, Andika Bagus Nur Rahma Andoko Andoko, Andoko Anwar Johari Aprilia Sari Yudha Arbin Janu Setiyowati, Arbin Ardianto Prasetiyo Arifiansyah, Gilang Putra Pratama Avita Ayu Permanasari Awalya Siska Pratiwi Bayu Angga Pratama Boedya Djatmika Busono, Milzam Rahmat Danang Priyasudana Dani Hari Tunggal Prasetiyo Darmawan, Muhammad Wahid Dewi Puspitasari Didin Zakaria Lubis Didin Zakariya Lubis Diki Dwi Pramono Djoko Kustono Eddy Rudianto Erry Yulian Triblas Adesta Fadhila Wahyu Putri Fitriyanto, Retnaldi Fuad Indra Kusuma Ghazali, Mariyam Jameelah Ginta, Turnad Lenggo Habiby, M. Nuril Anwar Hasan Ismail Heru Suryanto Hetti Rahmawati Hidayatullah, Hengki Tri Imam Muda Nauri ING Wardana Izzatus Tsamroh, Dewi Jaafar, Rosidah Jeefferie Abd Razak Kevin Valiant Cahya Komara, Erwin Kurniawan, Dany Ardymas Lorenzo, Gina A. M. Alfian Mizar M. Rizka Gita Firmansyah Maheswara, Dharma Mahfud Ihsan Majid Niaz Akhtar Malik Abdurrachman Mohamad, Noraiham Mohammad Tauviqirrahman Muhajir, Muhamad Muhamad Fatikul Arif Muhammad Hanis Zakariah Muhammad Hanish Zakariah Muhammad Ilman Hakimi Chua Abdullah Muhammad Kashif Muhammad Najib Mauludi Muhammad Rizka Gita Firmansyah Murdanto, Putut Mustapha, Mazli N. A. Ahmad Nanang Eko Wahyuningtyas Nanang Qosim Nandang Mufti Noraiham Mohamad Nur Aliza Ahmad Nursabrina, Aisya Pasang, Timotius Pasha, Muhammad Faizullah Pindo Tutuko Pramono, Diki Dwi Prasetya, Riduwan Prihanto Trihutomo Puput Risdanareni Purwanto, Muhammad Rizky Puspitasari, Dewi Radja, Muhammad Bustomi Razak, Jeefferie Abd Razak, Jeefferie Abd. Razak, Jeefferie Bin Retno Wulandari Retno Wulandari Reyhandi Katon Asmoro Riana Nurmalasari Rosidah Jaafar S. M. S. N. S. Zahari Salam, Haipan Samsudin Anis Saputro, Suratno Adi Simonne Andrean Crisdion Siti Nur Azella Zaine Siti Zaleha Wahid Solichin Solichin Solichin Solichin Sukarni Sukarni Sukarni Sukarni Sumarli Sumarli T. Pasang Wahid, Siti Zaleha Wahidin, Ahmad Faizal Wahono Wahono Wahyu Kurnianto Wahyunengsih, Wahyunengsih Warestu, Ayu Wati, Rita Fajar Widiyanti Widiyanti, Widiyanti Winarto Winarto Wiwik Wahyuni Yahya Zakaria Yazirin, Cepi