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Determination of Potassium in Empty Bunches Palm Oil (Elaeis guineensis Jacq.) Using Flame Photometry Method Alva, Sagir
Journal of Chemical Natural Resources Vol. 3 No. 2 (2021): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (326.621 KB) | DOI: 10.32734/jcnar.v3i2.9348

Abstract

Research on the determination of potassium in empty bunches palm oil have been done with the flame photometry method. The samples were taken randomly from five areas in Northen Sumatera with various heights in the range of < 25- 400 m above sea level. The first sampling was of Datuk Bandar district at Tanjung Balai < 25 m, Meranti district at Kisaran 50 to 100 m, Bosar Maligas district at Simalungun 150-200 m, Simarimbun district at Pematang Siantar 250 to 300 m, and the last Sari Matondang district at Sidamanik 350-400 m. The sample was digested using concentrated nitric aid and 30% hydrogen peroxide then heated with the addition of nitric acid concentrated. Potassium content was measured with a flame photometer at specific 767.5 nm by using calibration methods. The result obtained that potassium contents in the samples were 11.83%; 17.56%; 21.89%; 24.68%, and 25.14% for Tanjung Balai, Kisaran, Simalungun, Pematang Siantar, and Sidamanik respectively. The data obtained showed the higher area of the sea, the lower the temperature so the content of potassium increased in the palm oil empty bunches.
Determination of Level of Ag, Cu, and Fe in the Mineral Rock Coming from Jambu Dolok Hamlet Toba Samosir District Alva, Sagir
Journal of Chemical Natural Resources Vol. 3 No. 2 (2021): Journal of Chemical Natural Resources
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jcnar.v3i2.9355

Abstract

A study on the determination of Ag, Cu, and Fe contents in mineral rocks has been conducted. The sample was randomly taken from the surface of the hill at Dusun Jambu Dolok Kabupaten Toba Samosir. Ovens destroyed the sample at 900°C. For the determination of Ag and Cu, the sample was dissolved by using concentrated HNO3. For the determination of Fe, it was dissolved by using concentrated HNO3 and concentrated HCl. The determination of Ag, Cu, and Fe was carried out using Atomic Absorption Spectrophotometer. The wavelength is 328.1 nm for Ag, 324.7 nm for Cu, and 248.3 nm for Fe. The results obtained show that the content of Ag, Cu, and Fe in the sample are 2.1590 mg/Kg, 21,311.4754 mg/Kg, and 150,000.0000 mg/Kg, respectively
Evaluating Vegetable Oils as Eco-Friendly Alternatives in Metal Heat Treatment : Review sukendar, Sukendar; Alva, Sagir; Ginting, Dianta
Jurnal Teknik Mesin (Journal Of Mechanical Engineering) Vol 15, No 01 (2026)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/jtm.v15i01.37136

Abstract

Recent research on sustainable heat-treatment processes highlights the strong potential of vegetable oils as environmentally benign quenching media. This review integrates thermo-physical characteristics, cooling behavior, and mechanical performance reported in key studies from 2010–2024. Vegetable oils demonstrate higher quenching severity (H-value 0.17–0.21) than mineral oils (0.11–0.14), supported by stable viscosity ranges (20.78–110.35 cSt at 40°C; 6.9–33.65 cSt at 100°C) and superior thermal conductivity (0.131–0.182 W/m°C) relative to SAE40 (0.145 W/m°C). Their mechanical performance is consistently favorable: palm kernel oil yields hardness up to 40.85 HRC, cottonseed oil ~33.25 HRC, and groundnut oil produces ~173.8 HV with yield strength reaching 805 MPa. Neem seed oil exhibits exceptional hardness (68.7 HRA) and tensile strength (2122 MPa), while marula oil significantly enhances the hardness and tensile strength of medium-carbon steels. Soybean, sunflower, and canola oils applied to AISI 1045 steel deliver hardness levels of 41–50 HRC. Impact toughness also improves, with neem oil reaching 15 J and additive-modified quenchants containing 5% metal salts achieving up to 131 J. Antioxidant-fortified oils (Irganox L109, TBHQ, Propyl Gallate) further improve oxidation resistance without impairing cooling performance. Overall, properly stabilized vegetable oils represent robust, efficient, and environmentally responsible quenching alternatives for the heat treatment of low- and medium-carbon steels.
Preparation and Characterization of Chitosan/Titanium Dioxide Film for Electrochemical Sensing Applications Nasution, Astri Anjelina; Nainggolan, Irwana; Andriayani, Andriayani; Alva, Sagir
Journal of Technomaterial Physics Vol. 8 No. 1 (2026): Journal of Technomaterial Physics
Publisher : Talenta Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32734/jotp.v8i1.25063

Abstract

Chitosan/TiO₂-modified electrodes were characterized using the cyclic voltammetry method. The electrodes were fabricated through an electrodeposition technique to produce a coating on the substrate surface. TiO₂ concentrations of 50, 100, 150, 200, and 250 mg/L were used. The chemical structure and functional group interactions of the films were characterized using Fourier Transform Infrared (FTIR) spectroscopy, which revealed characteristic chitosan functional groups and Ti–O–Ti stretching bands, indicating the dispersion of TiO₂ within the chitosan matrix. The electrochemical performance of the electrodes was evaluated in phosphate-buffered saline (PBS) solution at pH 7. The results showed that the chitosan/TiO₂ concentration variation of 150 mg/L produced the highest anodic current response, while the optimum scan rate was obtained at 75 mV/s. A linear relationship between peak current and scan rate was obtained, with a regression equation of y = 0.0014x + 0.3788 and a coefficient of determination (R²) of 0.9869, indicating a strong linear correlation. Based on these results, the chitosan/TiO₂ material exhibited electrochemical responses with potential for further development in electrochemical sensing applications.
Co-Authors Adelfy Dara Arianti Agnes Hanna Patty, Armin Naibaho, Singgih Fitra Utama, Ahmad Ariri Ahmad Kamal Arifin Aiman Sajidah Abd Aziz Aiman Sajidah binti Abdul Aziz Albert Phak Jie Wong Alfian Noviyanto Ali Rinaldi Andi Firdaus Sudarma Andriayani Arianti, Adelfy Dara Arifin, Ahmad Kamal Ariri, Ahmad Asadullah, Mas'ud Asadullah, Masud Asep Setia Kristanto Baihaqi Baihaqi Basyari, Aziz Binawati Ginting Dafit Feriyanto Dayanti, Meri Deni Shidqi Khaerudini Dianta Ginting Edy Herianto Majlan Eka Safitri Eka Safitri Elin Yusibani Elly Sufriadi Fadhilla, Eky Nur Fadilah, Arif Fidi Fidi Fidi, Fidi Fitri , Muhammad Fitri Dara Fonna, Syafrizal Friliandita, Vivi Hadi Pranoto Hadi Pranoto Hasbullah, Siti Aishah I Gusti Ayu Arwati Ibdal Satar Imam Hidayat Indradewa, Rhian Iqhrammullah, Muhammad Julinawati Julinawati Julinawati, Julinawati Khairi Suhud KHAIRI SUHUD Kurniawan Kurniawan Leni Heliawati Maryani, Yeyen Marysca Shintya Dewi Mas&#039;ud Asadullah Mohd Ismahadi bin Syono Muhammad Farhan Muhammad Fitri, Muhammad Muhammad Isa Mustanir Mustanir Nanang Ruhyat Nasution, Astri Anjelina Noviyanto, Alvian Nurato , Nurato Nurul Islami, Nurul Pandriana, Aap Popy Yuliarty Pudjiwati, Sri Resista Vikaliana Resmi Bestari Muin Rinaldi, Ali Rini Anggraini Robi Suherman Rohadi Satrio Budi Utomo Sawarni Hasibuan Siti Aishah Hasbullah Subekti Subekti Suhud, Khairi Sukendar Sukendar Sukoma, Sukoma Sundari, Rita Supaat Zakaria Surbakti, Muhammad Syukri Suyadi, Yadi Swandya Eka Pratiwi Syafrizal Fonna Tarigan, Kontan Teddy Kurniawan Thasyah Pitanova Vivi Friliandita Wahyu Irwansyah Wahyudi, Haris Wan Adil bin Wan Jamil Wan Adil Wan Jamil Wiwit Suprihatiningsih Zakaria Zakaria Zulnazri, Z