Article Per Year (5 Year)
p-Index From 2021 - 2026
4.417
P-Index
This Author published in this journals
All Journal Traksi : Majalah Ilmiah Teknik Mesin Jurnal Pendidikan Teknologi dan Kejuruan Jurnal Sains Materi Indonesia SINTEK JURNAL: Jurnal Ilmiah Teknik Mesin ROTOR: JURNAL ILMIAH TEKNIK MESIN Widyariset Jurnal METTEK (Jurnal Ilmiah Nasional Dalam Bidang Ilmu Teknik Mesin) Science and Technology Indonesia Majalah Ilmiah Material, Komponen dan Konstruksi Jurnal AUDI Jurnal Rekayasa Material, Manufaktur & Energi Indonesian Journal of Chemistry NUSANTARA : Jurnal Ilmu Pengetahuan Sosial Majalah Ilmiah Pengkajian Industri Metalurgi Jurnal Metalurgi dan Material Indonesia Journal of Engineering and Scientific Research (JESR) Piston: Journal of Technical Engineering Widyariset Teknomekanik Indonesian Journal of Engineering and Science (IJES) Journal of Materials Exploration and Findings Malcom: Indonesian Journal of Machine Learning and Computer Science Metalurgi Jurnal Sains Materi Indonesia Recent in Engineering Science and Technology
Rini Riastuti, Rini
Departemen Teknik Metalurgi Dan Material, Fakultas Teknik, Universitas Indonesia, Depok
Aerospace Engineering Astronomy Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture 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 Immunology & microbiology Industrial & Manufacturing Engineering Library & Information Science Materials Science & Nanotechnology Mechanical Engineering Neuroscience Physics Transportation

Published : 60 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 60 Documents
Search

 2   3   4   5   6 
Morphological and Crystallinity Studies of Nanofiber Cellulose Based on Sargassum sp. Using Multistep Preparation Nurhayati, Nurhayati; Irianto, Hari Eko; Chalid, Mochamad; Riastuti, Rini
Indonesian Journal of Chemistry Vol 25, No 4 (2025)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.104211

Abstract

This study aims to investigate the crystallinity and morphological characteristics of cellulose nanofibers (CNF) isolated from Sargassum seaweed through a multistep preparation. The isolation was conducted in stages, including alkalinization, bleaching, and mechanical reduction in fiber size. In addition to observing the outcomes at each isolation stage, three mechanical processes were implemented to generate CNF. The observed parameters included fiber morphology analyzed using scanning electron microscopy (SEM) and fiber crystallinity tested using X-ray diffraction (XRD). The results indicated that Sargassum mostly exhibits a type Iα structure of cellulose. The multistep treatment, combined with mechanical processing, resulted in finer fibers and an improved crystallinity index, reaching a maximum value of 70.39%. These findings suggest that cellulose nanofibers from Sargassum have the potential to be used in sustainable biomedical materials.
MENINGKATKAN KEMAMPUAN SAINS MELALUI PERMAINAN WARNA DENGAN MENGGUNAKAN CAT AIR PADA ANAK KELOMPOK B TK NEGERI PEMBINA KABUPATEN TEMANGGUNG Riastuti, Rini
Jurnal AUDI: Jurnal Ilmiah Kajian Ilmu Anak dan Media Informasi PAUD Vol 3 No 2 (2018): Desember
Publisher : UNIVERSITAS SLAMET RIYADI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33061/ad.v3i2.2734

Abstract

Tujuan dari penelitian ini adalah 1) untuk mengetahui pelaksanaan pembelajaran permainan warna dengan menggunakan cat air dalam meningkatkan kemampuan sains anak, 2) untuk mengetahui peningkatan kemampuan sains pada anak setelah kegiatan permainan warna dengan menggunakan cat air di Kelompok B TK Negeri Pembina Kabupaten Temanggung Semester I Tahun Pelajaran 2017/2018. Berdasarkan hasil penelitian dan pembahasan, maka dapat disimpulkan bahwa kemampuan sains anak Kelompok B TK Negeri Pembina Kabupaten Temanggung dari kondisi awal sampai dengan dilaksanakannya perbaikan pembelajaran sampai dengan Siklus II telah mengalami peningkatan yang sangat signifikan.  Pada kondisi awal, anak yang mampu menunjukkan kemampuan sainsnya hanya 3 anak (20%) dari 15 anak. Berdasarkan perbaikan pembelajaran yang diperoleh pada Siklus I, maka dapat dilihat hasil penelitian bahwa anak yang mampu melaksanakan permainan  warna dengan kriteria berkembang sesuai harapan 7 anak (46,7%), mulai berkembang 2 anak (13,3%), dan belum berkembang 6 anak (40%). Setelah diadakan perbaikan pembelajaran pada Siklus II anak yang dianggap mampu dengan kriteria berkembang sesuai harapan 13 anak (86,8%), mulai berkembang 1 anak (6,6%), belum berkembang 1 anak (6,6%) dan telah mencapai standar ketuntasan belajar yang telah ditetapkan dengan kriteria anak tertarik dalam kegiatan bermain warna, anak mampu mencampur warna dengan baik, dan anak mampu menjawab pertanyaan dari peneliti.
Prediksi Sisa Umur Layan dan Analisa Resiko pada Power Transformer Menggunakan pendekatan Distribusi Weibull dan Risk Priority Number: Prediction of Remaining Service Life and Risk Analysis on Power Transformers Using The Weibull Distribution and Risk Priority Number Approach Rahardian, Krisnandha; Riastuti, Rini; Zakiyuddin, Ahmad
MALCOM: Indonesian Journal of Machine Learning and Computer Science Vol. 4 No. 1 (2024): MALCOM January 2024
Publisher : Institut Riset dan Publikasi Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.57152/malcom.v4i1.1068

Abstract

Transformator adalah peralatan mahal dan krusial dalam sistem transmisi dan distribusi tenaga listrik. Berperan penting dalam menjaga keandalan dan efisiensi pasokan listrik, transformator terus menerima tekanan termal, listrik, mekanik, dan kimia selama operasinya. Oleh karena itu, penilaian penuaan transformator memerlukan parameter komprehensif, terutama karena panas terbuang menjadi faktor pembatas untuk beban maksimum. Kelangsungan operasional transformator menjadi isu penting, dan kegiatan pemantauan, inspeksi, dan pemeliharaan rutin diperlukan untuk mencegah pemadaman yang tidak diinginkan. Dalam penelitian ini, pendekatan dilakukan dengan mendekomposisi transformator menjadi bagian-bagian dan melakukan analisis risiko kuantitatif serta evaluasi prioritas. Lowest Replacable Unit (LRU) dievaluasi menggunakan Weibull++, Life Data Analisis, dan software reliasoft. Hasil analisis menunjukkan bahwa Power Transformer (TR-01) milik PT ABC di Area Integrated Terminal berada dalam kondisi baik dan layak beroperasi. Simulasi Weibull++ menunjukkan umur sisa 275 bulan (22.9 tahun), dengan reliabilitas 86% untuk 4 tahun ke depan dan nilai risk priority number Medium High (3D). Kesimpulan dari analisis ini memberikan keyakinan bahwa transformator berfungsi dengan baik dan dapat diandalkan dalam operasionalnya.
Effect of 2-Methylimidazole Composition as Low-Temperature Application in Phenol-Formaldehyde, Glycidyl Ether Epoxy Coating Paltgor, Rinush Fedrikdo; Riastuti, Rini; Ramdhani, Rizal Tresna; Yunus, Muhammad
Jurnal Sains Materi Indonesia Vol. 25 No. 1 (2023): Jurnal Sains dan Materi Indonesia
Publisher : BRIN Publishing (Penerbit BRIN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/jsmi.2023.267

Abstract

The addition of materials to pile pipe at low temperatures is very challenging. Thereby, an optimum operating level is needed to produce a quality coating. Furthermore, 2-methylimidazole (2MI) was added into a phenol-formaldehyde, glycidyl ether polymer fusion bonded epoxy (FBE) coating at different concentrations of 1, 2, and 3 %wt. Thermal analysis was then carried out using differential scanning calorimetry (DSC), where the addition of 2MI decreased the curing temperature to 134.76°C due to the reduced activation energy. Potentiodynamic polarization showed the best corrosion rate of 0.00991 mm/year with a current density of 0.847μA/cm2 after adding 1 %wt 2MI. Electrochemical impedance spectroscopy (EIS) was carried out to determine the charge transfer resistance and maximum coating capacitor capacitance after adding 1 %wt 2MI, namely 9.9 kΩ and 8.45×10-5 F, respectively. The cathodic disbondment test (CD-Test) showed that the disbondment radius of the coating under the influence of the cathodic protection current was 4.32mm. Mechanical analysis by pull-off adhesion test showed a value of 7.28 MPa after the addition of 2MI 2 %wt but decreased to 6.63 MPa at 3 %wt. Therefore, the optimum addition is 1 %wt 2MI for low-temperature applications of 170 –175°C in piles with high coating performance and compliance with predetermined standards.
Corrosion behavior of super austenitic stainless steel, Duplex 2205 and 316L in sulfamic acid environment Roszardi, Bashari Rohululloh; Riastuti, Rini; Budiarto, Wahyu; Darsono, Nono; Syahid, Adi Noer
Jurnal Pendidikan Teknologi Kejuruan Vol 4 No 4 (2021): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jptk.v4i4.24323

Abstract

Currently, sulfamic acid as a primary chemical industrial material is ubiquitous. One of its uses is a sweetener. Due to its corrosive nature, it is necessary to use a suitable container to avoid contamination of the solution. Corrosion behavior of super austenitic stainless steel, duplex 2205, and 316L uncovered to sulfamic acid in diverse attention at ambient temperature had been investigated. Concentration Weight loss method, Potentiodynamic Polarization, and Electrochemical Impedance Spectroscopy (EIS) examined the corrosion rate. The result showed that the corrosion rate of material increased with the increasing concentration of sulfamic acid. Super austenitic stainless steel has higher corrosion resistance than duplex 2205 and 316L.
Anticorrosive Epoxy Coatings Enhanced with Rice Husk Derived-Graphene Amalia, Dinda Putri; Riastuti, Rini
Jurnal Pendidikan Teknologi Kejuruan Vol 5 No 2 (2022): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jptk.v5i2.26823

Abstract

Coatings are the most common corrosion control practice. Therefore, it is very important to discover the most cost-effective and environmentally-friendly coating materials for sustainability. When dispersed in epoxy resin, graphene has barrier properties that improve the anticorrosive performance of the metal significantly. Graphene can be synthesized from agricultural waste. Herein, graphene derived from rice husk and epoxy resin was developed with solution mixing to prepare graphene-epoxy coating composites with enhanced anti-corrosive properties. X-ray diffraction, UV-vis spectroscopy, and scanning electron microscopy were used to characterize the synthesized graphenes. The anticorrosive properties of the coatings were characterized by potentiodynamic polarization and electrochemical impedance spectroscopy, which resulted in the corrosion resistance of synthesized graphene and commercial reduced graphene oxide being better than commercial graphene. The impedance and corrosion rate values of synthesized graphene are 1.77 x 105 Ω and 0.00011 mm/year.
Corrosion failure analysis of CuNi 90/10 on seawater fire protection system Riastuti, Rini; Alfian, Alfian; Manurung, Rizky Rama Putra; Budiarto, Wahyu; Kaban, Agus S
Jurnal Pendidikan Teknologi Kejuruan Vol 5 No 4 (2022): Regular Issue
Publisher : Universitas Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24036/jptk.v5i4.30423

Abstract

The failure analysis of a seawater fire protection system of oil and gas processing facility was observed in this paper. The fire protection pipe line & hull seawater filter were made of CuNi 90/10. Severe deep pits and fracture were observed at bottom of jockey pump spool pipe and hull seawater filter. Visual observation, scanning electron microscope, energy dispersive spectroscopy, x-ray diffractometry were employed in the present failure analysis. The oxygen exposure on CuNi 90/10 of Seawater Fire Protection system had a significant impact on failure and was exacerbated by the presence of chloride exposure.
CORROSION BEHAVIOR OF SUPER AUSTENITIC STAINLESS STEEL, DUPLEX 2205 AND 316L IN SULFAMIC ACID ENVIRONMENT Roszardi, Bashari R; Riastuti, Rini; Budiarto, Wahyu; Darsono, Nono; Syahid, Adi Noer
NUSANTARA : Jurnal Ilmu Pengetahuan Sosial Vol 9, No 2 (2022): NUSANTARA : Jurnal Ilmu Pengetahuan Sosial
Publisher : Universitas Muhammadiyah Tapanuli Selatan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31604/jips.v9i1.2022.85-91

Abstract

Currently, sulfuric acid as a primary chemical industrial material is ubiquitous. One of its uses is a sweetener. Due to its corrosive nature, it is necessary to use a suitable container to avoid contamination of the solution. Corrosion behavior of super austenitic stainless steel, duplex 2205, and 316L uncovered to sulfamic acid in diverse attention at ambient temperature had been investigated. Concentration Weight loss method, Potentiodynamic Polarization, and Electrochemical Impedance Spectroscopy (EIS) examined the corrosion rate. The result showed that the corrosion rate of material increased with the increasing concentration of sulfamic acid. Super austenitic stainless steel has higher corrosion resistance than duplex 2205 and 316L.  
Effect of Impurities in Supercritical CO2 Environment on Steel Corrosion Behavior – an Overview Widianto, Shilla Rizqi; Soedarsono, Johny Wahyuadi; Riastuti, Rini; Munir, Badrul
Journal of Materials Exploration and Findings Vol. 3, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Carbon capture, utilization, and storage (CCUS) technology is one of the available technologies to reduce presence of greenhouse gasses. Implementation of CCUS technology strongly relates with the CO2 transportation from the capturing facility to the storage in the geological reservoir. The most economical method for large-scale and long-distance CO2 transportation is using pipeline in supercritical phase. Moreover, presence of impurities such as water, O2, SO2, H2S, NO2 may cause detrimental effect towards carbon steel pipeline. This paper intends to provide an initial information for supercritical CO2 pipeline material selection, which review and summarize existing research on corrosion under supercritical CO2 environment. This paper present environment categorization in supercritical CO2 stream, impurities effect toward sample, as well as brief discussion about corrosion evaluation method.
Feasibility Study of Using Energy Extracted from The Process of Electrochemically Consumed of Al 2024 for Powering Daily Used Electric Car Marda, Yanuar Mohamad; Riastuti, Rini; Ibrahim, Muhammad Hamka
Journal of Materials Exploration and Findings Vol. 3, No. 2
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Usage of green energy for transportation has become important due to the contribution of transportation activity to climate change. Electrochemical energy has been used as a source of green energy. The objective of this work is to evaluate sufficiency of energy provided by electrochemically consumed Al 2024 for supplying energy to daily used PHEV electric car. Study of previous articles, observation of typical amount of energy required, electrochemical galvanic cell experiments, and simple calculations have been conducted to determine produced energy feasibility. Electrical energy produced by consuming 340 gr of Al 2024 in galvanic cells has the total lifetime of 10.8 hours and the mileage covered on the electric vehicle mode is 234.9 km. It can be used to cover most of the energy needed for a daily combination of sub-urban and urban city car.
Co-Authors Abdullah, Abdul Halim Adam Hidana Yudo Saputro, Adam Hidana Yudo Adi Noer Syahid Adipurnama, Iman Agus Supriyanto Ahmad Fadli Ahmad Fadli Ahmad Maksum Ahmad Zakiyuddin Akhmad Faizal Alfian Alfian Amalia, Dinda Putri Amanda, Putri Amin Suhadi Amin Suhadi Amin Suhadi Amin Suhadi Amin Suhadi Amin Suhadi, Amin Andryansah Andryansah Anjar Oktikawati Aqila, Daffa Aulia, Hafiz Ayu Rizeki Ridhowati Ayu Rizeki Ridhowati Azizah Intan Pangesty Badrul Munir, Badrul Bashari R Roszardi Baskoro, Agung budiarto, wahyu Chalid, Muchamad Dedi Priadi Dedi Priadi Dedi Priadi Dedi Supriadi Diana Natalia Eka Febriyanti Eka Febriyanti Eka Febriyanti Eka Febriyanti Eka Febriyanti Eka Febriyanti Eka Febriyanti Eka Febriyanti Febi Dwi Antony Febriyanti, Eka febriyanti, eka febriyanti, eka Gadang Priyotomo Gadang Priyotomo Hari Eko Irianto Ibrahim, Muhammad Hamka Ifah Munifah Irawan, Januar IRWAN WIJAYA J.W. Soedarsono Jamal Basmal, Jamal Jamhari Jamhari Johny Wahyuadi Soedarsono Kaban, Agus S Kautsar Muwahhid Kautsar Muwahhid Kusumaningrum, Wida Banar Manurung, Rizky Rama Putra Marda, Yanuar Mohamad Mega Herawati Arifiana Amanah Notonegoro, Mega Herawati Arifiana Amanah Mhd. Ibkar Yusran Asfar Mochamad Chalid Muhammad Refai Muslih Muhammad Rifai Muhammad Yunus Muhammad Yunus Najmudin, Muhammad Guruh Nikitasari, Arini Nono Darsono Nono Darsono, Nono Nurhayati Nurhayati Nurhayati Paltgor, Rinush Fedrikdo Putri Salsabila, Syanatha Rachmat Hermawan Rahardian, Krisnandha Ramadhani, Rizal T Ramadhani, Rizal Tresna Ramdhani, Rizal Tresna Riady, Rado Ridhowati, Ayu Rizeki Ridhowati, Ayu Rizeki Rinta Kusumawati, Rinta Rinush Fedrikdo Paltgor Rizal Tresna Ramdhani Roszardi, Bashari R Roszardi, Bashari Rohululloh Roziafanto, Ahmad Nandang Santoso, Irwan Wijaya SATRIYAS ILYAS Sunarso Sunarso Syahid, Adi Noer Tiggor, Triadhi Panthun Tri Handayani Tri Hardi Priyanto Wahyu Budiarto Widianto, Shilla Rizqi Winarto Winarto Yuanto, Nursidi