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All Journal TEKNIK Teknika Jurnal Penelitian Fisika dan Aplikasinya (JPFA) Jurnal Sains Materi Indonesia JFA (Jurnal Fisika dan Aplikasinya) Science and Technology Indonesia Biodidaktika : Jurnal Biologi dan Pembelajarannya Jurnal SOLMA Jurnal Teori dan Aplikasi Fisika Jurnal Fisika Indonesia Jurnal Riset Teknologi Pencegahan Pencemaran Industri Journal of Energy, Material, and Instrumentation Technology NEAR: Jurnal Pengabdian kepada Masyarakat
Marjunus, Roniyus
Department Of Physics, Faculty Of Mathematics And Natural Sciences, University Of Lampung, Bandar Lampung
Humanities Astronomy Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Earth & Planetary Sciences Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Health Professions Immunology & microbiology Languange, Linguistic, Communication & Media Library & Information Science Materials Science & Nanotechnology Nursing Physics Public Health Social Sciences Transportation Other

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Processing of granite quarry solid waste into industrial high silica materials using leaching process with HCl concentration variation Hendronursito, Yusup; Amin, Muhammad; Sumardi, Slamet; Marjunus, Roniyus; Clarasati, Frista; Birawidha, David Candra; Muttaqqi, Muhammad Al; Isnugroho, Kusno
Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol. 11 No. 2 (2020)
Publisher : Balai Besar Standardisasi dan Pelayanan Jasa Pencegahan Pencemaran Industri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21771/jrtppi.2020.v11.no2.p43-50

Abstract

This study was aimed to increase granite's silica content using the leaching process with HCl concentration variation. The granite used in this study came from Lematang, South Lampung. This study aims to determine the effect of variations in HCl concentration, particle size, and rotational speed on the crystalline phase and chemical elements formed in the silica product produced from granite. The HCl concentration variations were 6.0 M, 7.2 M, 8.4 M, and 9.6 M, the variation in particle size used was 270 and 400 mesh. Variations in rotational speed during leaching were 500 and 750 rpm. Granite powder was calcined at 1000 ºC for 2 hours. Characterization was performed using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP- OES). The results showed that the silica content increased with increasing HCl concentration, the finer the particle size, and the higher the rotational speed. XRF analysis showed that the silica with the highest purity was leached with 9.6 HCl with a particle size of 400 mesh and a rotational speed of of 750 rpm, which was 73.49%. Based on the results above, by leaching using HCl, the Si content can increase from before. The XRD diffractogram showed that the granite powder formed the Quartz phase.
Pengaruh Laju Penginjeksian Doping Fluor terhadap Aktivitas Fotokatalis Nanotitania Menggunakan Metode Sol Gel Rahayu, Sri; Manurung, Posman; Marjunus, Roniyus
Jurnal Teori dan Aplikasi Fisika Vol 8, No 2 (2020): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v8i2.2253

Abstract

The titania synthesis of fluorine doping (F-TiO2) was carried out through the sol-gel method. Titanium isopropoxide (TTIP), tween-80, isopropanol and ammonium fluoride (NH4F) as sources of doping fluorine were used as the main ingredients. This research aimed to study the effect of fluorine doping injection rate using injection pumps on F-TiO2 photocatalyst activity. Four fluorine doping samples were prepared with the respective penetration rate of 0.4 ml / 30 minutes; 0.4 ml / 60 minutes; 0.4 ml / 90 minutes  and 0.4 ml / 120 minutes. The titania powder was calcined at 450 oC for 5 hours. The sintered sample was tested for photodegradation of remazol yellow under UV light. Physical characteristics were analyzed using transmission electron microscopy (TEM) and Uv-Vis spectrophotometer. The results of the UV-Vis spectrophotometer showed that the particle size of samples with an injection rate of 0.4 ml / 90 minutes showed higher photocatalyst activity with particle sizes of (14 nm ± 4 nm).
Analysis of Fine Glass Waste Addition as a Filler Material for Sand Substitution on the Properties of Mortar Products Suharto, Suharto; Amin, Muhammad; Al Muttaqii, Muhammad; Marjunus, Roniyus; Fitri, Nuzullia; Suhartono, Suhartono
TEKNIK Vol 42, No. 3 (2021): December 2021
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/teknik.v42i3.32686

Abstract

Inorganic glass waste can replace sand in mortar production due to its SiO2 content being greater than 70%. This study aims to analyze the increase in mortal product agility due to the substitution of sand and reducing environmental pollution. The fine glass waste used is restrained on 80 and 120 mesh sieves. The fine glass waste substitution variations are 0, 10, 20, 30, 40, and 50% of the sand weight. The results show that fine glass waste could be used as a material for sand substitution because of the content of SiO2 of 73.8%. The results from XRD indicate that the phase of fine waste glass is amorphous. The mortar was printed with a 5x5x5 cm cube mold, and it was soaked for 7, 14, and 21 days. Based on the results, the compressive strength with a high value of 13.58 MPa at 20% fine glass waste substitution and 120 mesh. The density of 2.8±0.8 g/cm3, porosity 4.40±0.001%, and absorption 2.83±0,0009%. The compressive strengths, density, porosity, absorption, XRF and XRD characterization were evaluated. The results showed that the SiO2 compound in waste glass with the right composition of 20% could significantly increase the compressive strength. Phase formation of Calcite (CaCO3), Quartz (SiO2), and Portlandite (Ca(OH)2) was formed from the results of XRF characterization
Design of an Earthquake Intensity Estimation System for Early Warning Trismahargyono Trismahargyono; Sri Ratna Sulistiyanti; Roniyus Marjunus
Jurnal Teori dan Aplikasi Fisika Vol 9, No 2 (2021): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v9i2.2803

Abstract

Indonesia is located at the junction of three tectonic plates and has many active faults. The consequence of this tectonic arrangement makes Indonesia prone to earthquakes. Therefore, earthquake mitigation efforts based on an early warning system need to be done. The design of an earthquake strength estimation system, based on python, for this early warning, analyzes the initial phase of the first three seconds since the arrival of the P wave, using parameters in the form of Pd (the maximum amplitude of the first three seconds of the arrival of the P wave). The resulting tools and systems consist of hardware in the form of Raspberry Pi3B + and ADXL345. The system will detect in real time and automatically trigger an earthquake using the STA / LTA method. When the Pd and Td parameters have been obtained, the system will calculate and issue earthquake strength information, in the form of magnitude and intensity scale of earthquake damage MMI (Modified Mercally Intensity), which will then be sent automatically via the telegram application. Testing of tools and systems was carried out in an earthquake simulator, using the Padang earthquake parameters on 30 September 2009, 17:16:09 WIB. The results of the test produce an intensity scale of VIII MMI, these results are close to the results of the BMKG for the earthquake, with an intensity scale of VIII MMI.  From these results the designed tools and systems can be used to provide early warning in the event of an earthquake.
Pengaruh Penambahan Abu Sekam Padi Terhadap Sifat Fisis dan Mekanis pada Mortar Ahmad Munawir Siregar; Roniyus Marjunus; Simon Sembiring
Jurnal Teori dan Aplikasi Fisika Vol 8, No 1 (2020): Jurnal Teori dan Aplikasi Fisika
Publisher : Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtaf.v8i1.2309

Abstract

The research was carried out about the effect of adding rice husk ash to physical and mechanical properties of mortar. Mortar was moulded with three composition comparisons between ordinary portland cement, rice husk ash, and rice stalk fiber. Rice husk ash was burned at temperature of 700 OC for 2 hours, rice stalk fiber was mechanically sliced up to 0.8 mm in size, then mortar molding and maintenance was processed for 28 days. The mortars that had reached the age of 28 days were tested according to the  Indonesia National Standard (SNI) including physical properties (water absorption, density), and mechanical properties (compressive strength, modulus of elasticity, modulus of rupture). Characterization of microstructure, morphology and counting all elements on the surface of  mortar were processed by using Scanning Electron Microscopy - Energy Dispersive X-ray Spectroscopy (SEM-EDS). The results of research that had been carried out, mortar with the most optimum physical and mechanical properties was mortar B with a composition of 65%: 10%: 25%. The results of the characterization using SEM-EDS showed that the surface of mortar B was better with grain diameter (1.4 ± 0.9) µm and the most dominant element in the mortar was element of Ca and Si which functioned as mortar binder and hardener.
PEMANTULAN DAN PEMBIASAN GELOMBANG ELEKTROMAGNET HARMONIK PERTAMA (FHEM) TERPOLARISASI-S DI BIDANG BATAS BAWAH BAHAN ANTIFEROMAGNETIK FeF2 PADA KONFIGURASI VOIGT Taufik Nurrohman; Roniyus M. S.
Jurnal Sains Materi Indonesia Vol 5, No 1: OKTOBER 2003
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (484.352 KB) | DOI: 10.17146/jusami.2003.5.1.5217

Abstract

PEMANTULAN DAN PEMBIASAN GELOMBANG ELEKTROMAGNET HARMONIK PERTAMA (FHEM) TERPOLARISASI-S DI BIDANG BATAS BAWAH BAHAN ANTIFEROMAGNETIK FeF2 PADA KONFIGURASI VOIGT. Telah dilakukan analisis teoretis mengenai pemantulan dan pembiasan gelombang elektromagnet harmonik pertama (FHEM) terpolarisasi-s di bidang batas bawah bahan antiferomagnetik FeF2 pada konfigurasi Voigt. Dari penelitian ini didapatkan informasi bahwa reflektansi (R) dan transmitansi (T) gelombang elektromagnet harmonik pertama di bidang batas bawah memiliki sifat tak resiprokal terhadap perubahan tanda HO (medan magnet konstan terpasang dari luar) maupun terhadap perubahan tanda sudut Φ(sudut tiba gelombang datang), sama seperti sifat-sifat yang diperoleh di bidang batas atas. Selain itu diperoleh juga relasi V1(Ho) = V2(-Ho) dan V1(Φ) = V2(-Φ) dengan V1 dan V2 berturut-turut adalah R dan T di bidang batas atas dan bidang bawah.
PERHITUNGAN REFLEKTANSI DAN TRANSMITANSI GELOMBANG ELEKTROMAGNET HARMONIK KEDUA TERPOLARISASI-S PADA BAHAN ANTIFEROMAGNET FeF2 DALAM KONFIGURASI FARADAY Roniyus M. S.; Muslim Muslim; Kamsul Abraha
Jurnal Sains Materi Indonesia Vol 5, No 1: OKTOBER 2003
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1137.509 KB) | DOI: 10.17146/jusami.2003.5.1.5214

Abstract

PERHITUNGAN REFLEKTANSI DAN TRANSMITANSI GELOMBANG ELEKTROMAGNET HARMONIK KEDUA TERPOLARISASI-S PADA BAHAN ANTIFEROMAGNET FeF2 DALAM KONFIGURASI FARADAY. Telah dilakukan perhitungan reflektansi dan transmitansi gelombang elektromagnet harmonik kedua terpolarisasi-s pada bahan antiferomagnet FeF2 dalam konfigurasi Faraday. Gelombang elektromagnet harmonik kedua (SHEM) yang terpantul dan terbias ini sangat dipengaruhi oleh gelombang elektromagnet harmonik pertama yang terpantul dan terbias yang dibangkitkan oleh gelombang datang. Prosentase dari pemantulan dan pembiasan gelombang SHEM ini lebih kecil daripada gelombang harmonik pertama. Dari perhitungan ini didapatkan informasi bahwa perbandingan antara R(2)/T1(2) dan T2(2)/T1(2) dengan R(2),T1(2) dan T2(2) berturut-turut adalah reflektansi gelombang SHEM, transmitansi gelombang SHEM yang terbias pertama dan transmitansi gelombang SHEM yang terbias kedua, memiliki sifat resiprokal terhadap perubahan tanda φ(sudut tiba gelombang datang terhadap garis normal) dan Hφ (medan magnet konstan terpasang dari luar).
Synthesis and characterization of TiO2 from Lampung’s Iron Sand using Leaching Method with Temperature Variation Iqbal Firdaus; Anggi Stevani; Yudhistira Novita Handayani; Nadia Febriyanti; Roniyus Marjunus; Posman Manurung
Jurnal Fisika dan Aplikasinya Vol 17, No 2 (2021)
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat, LPPM-ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j24604682.v17i2.7921

Abstract

Ilmenite is a natural material in the form of sand which contains heavy metal minerals that are very abundant in Lampung province. This research aims to determine the content of TiO2 from Lampungs iron sand by leaching method with temperature variation. The iron sand are mixed with sodium hydrogen carbonate (NaHCO3), then heated at 700◦C for an hour. This research uses 5 samples with leaching temperature variation of 70, 80, 90, 100, and 110◦C for 2 hours. The acid leaching process uses HCl 12 M with a ratio of iron sand and HCl of 1:4, while the water leaching process uses 50 ml of distilled water. Furthermore, the samples are characterized using XRD and XRF to determine TiO2 content in the iron sand. The result shows that the highest amount of TiO2 is obtained in the sample with the leaching temperature of 110◦C for 2 hours, which is approximately 61%.
Pengaruh Variasi Kadar CaCO3 terhadap Pertumbuhan Fase Superkonduktor BPSCCO–2212 Menggunakan Metode Pencampuran Basah Rianggi Wahyuni Pratiwi; Suprihatin; Simon Sembiring; Roniyus Marjunus
Journal of Energy, Material, and Instrumentation Technology Vol 2 No 1 (2021): Journal of Energy, Material, and Instrumentation Technology
Publisher : Departement of Physics, Faculty of Mathematics and Natural Sciences, University of Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1135.874 KB) | DOI: 10.23960/jemit.v2i1.37

Abstract

This research was conducted to determine the effect of CaCO3 levels on the formation of superconducting phase BPSCCO - 2212 by calculating the level of purity of the phases formed and looking at the microstructure. The variation of CaCO3 was 0.95, 1.00, 1.05 and 1.10 mole using the wet mixing method. The samples were calcined at 800 ° C for 10 hours, and sintered at 820 ° C for 20 hours. Synthesized samples were characterized using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The XRD’s chacterization results show that the level of purity of the formed phases increases with increasing Ca levels with maximum point at BPSCCO-2212/1.10 mole. The highest volume fraction was 79,06% in the BPSCCO-2212/1.10 sample. While the lowest volume fraction was 72.10% in the BPSCCO-2212/0.95 sample. Meanwhile, the highest degree of orientation was 20.59% at BPSCCO-2212/0.95. The lowest degree of orientation was 8.46% at BPSCCO-2212/1.10. SEM’s chacterization results show of all samples have been oriented altought not perfect yet and have relatively little space between slabs (voids).
Penggunaan Metode Taguchi untuk Menentukan Kondisi Parameter Optimum Pada Pembuatan CaO dari Batu Kapur (CaCO-3) Lilik Widia; Roniyus Marjunus; Sudibyo
Journal of Energy, Material, and Instrumentation Technology Vol 2 No 1 (2021): Journal of Energy, Material, and Instrumentation Technology
Publisher : Departement of Physics, Faculty of Mathematics and Natural Sciences, University of Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (456.707 KB) | DOI: 10.23960/jemit.v2i1.46

Abstract

Research has been carried out to determine the optimum conditions for making quicklime (CaO) using the Taguchi Method. CaO is the burning result of limestone (CaC ) in calcination process by releasing of C  gas until CaO solids occur. The limestone was calcined at .  The Taguchi Method is a quality improvement technique with the selection of the most influential parameters of the making of process CaO. The parameters are particle size, CaO mass, heating temperature and stirring time. The XRF results show that the levels of CaO after the Taguchi Method design has increased from 98.779% to 98.814%. The XRD results show that the CaO phase is amorphous. The phase which were formed by calcination are Lime (CaO), Quartz (Si ) and Hematite ( ). Based on the SEM results, the morphology of CaC  has an irregular particle size and tends to be a granular solid due to the presence of impurity. Meanwhile, the results of the EDS analysis show that the content of Calcium (Ca) is quite high. From the design results of the Taguchi Method, the optimum conditions is obtained at a particle size of 140 mesh, 75 gr CaO mass, heating temperature  and stirring time 0,5 hour.
Co-Authors Adi Saputra Agus Riyanto Agus Riyanto Agustrina, Rochmah Ahmad Munawir Siregar Ahmad Rosadi Al Muttaqii, Muhammad Amanto Amanto Amir Supriyanto Anggi Stevani Birawidha, David Candra Clarasati, Frista Diah Purwarini Dita Rahmayanti Dwi Asmi Dwi Asmi Ediman Ginting Ediman Ginting Suka Endarmoko - Fitri, Nuzullia Fuadiyah, Nadhifatul Heningtyas, Yunda Heri Satria Humairoh Ratu Ayu Imam Prayogi Indah Pratiwi Iqbal Firdaus Irvana, Raihan Isnugroho, Kusno Junaidi - Junaidi Junaidi Junaidi Junaidi Junaidi Junaidi Kamisah Delilawati Pandiangan Kamsul Abraha Karo , Pulung Karo Lilik Widia Mahfut Malik, Daffa Abdul Muhammad Amin Muhammad Amin Muhammad Rizki Muslim Muslim Muttaqqi, Muhammad Al Nadia Febriyanti Nanda Efbriyansyah Posman Manurung Pulung Karo-Karo Putri, Aprilia Eka Rahayu, Sri Rianggi Wahyuni Pratiwi Rio Orlando Pratama Setyawan, Dodi Yudo Simon Sembiring Simon Sembiring Slamet Sumardi, Slamet Solly Aryza Sri Ratna Sulistiyanti Sri Wahyu Suciyati Sudibyo Suharto Suharto Suharto Sumaryo Sumaryo Sumaryo Suprihatin Surtono, Arif Sutopo Hadi Syafiadi Syafriyadi Syafriadi Syafriadi Syaifudin Syaifudin Taufik Nurrohman Tiara Widiastuti Trismahargyono Trismahargyono Ulfa Nurini Warsito Warsito Wawan Rustyawan Yanti Yulianti Yanti Yulianti Yanti Yulianti Yudhistira Novita Handayani Yugo Chambioso Yusup Hendronursito Yusup Hendronursito, Yusup