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All Journal JURNAL KIMIA SAINS DAN APLIKASI PROSIDING SEMINAR KIMIA Jurnal Kimia Mulawarman E-Dimas: Jurnal Pengabdian kepada Masyarakat Akta Kimia Indonesia Chemistry Indonesian Journal of Chemical Research Molluca Journal of Chemistry Education (MJoCE) AKM: Aksi Kepada Masyarakat
Allo, Veliyana Londong
Jurusan Kimia, Fakultas Matematika Dan Ilmu Pengetahuan Alam, Universitas Mulawarman
Religion Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Decision Sciences, Operations Research & Management Education Engineering Environmental Science Social Sciences Other

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PIROLISIS SABUT KELAPA (Cocos nucifera L) MENGGUNAKAN INSTRUMEN PYROLYSIS-GAS CHOMATOGRAPHY/MASS SPECTROMETRY (PY-GC/MS) Noor Afdaliah; RR Dirgarini Julia Nurlianti Subagyono; Veliyana Londong Allo
PROSIDING SEMINAR KIMIA Vol 1 No 1 (2022): Prosiding SNK 2022
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Pyrolysis of a coconut (Cocos nucifera L) husk using a pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) instrument was carried out. This research was conducted to determine the chemical composition of pyrolysis of a coconut husk at temperaturs of 350, 450 and 550 °C. Pyrolysis of coconut husk produced lignin derivative products by 15-32% and cellulose/hemicellulose derivative products 9-34%. The gas product produced in the co-pyrolysis of a mixture microalgae anda coconut fiber is 41-50%. Pyrolysis product with the highest % area, namely methyl alcohol, 2-butanone, phenol, benzofuran, 2,3-dihydro- dan 2-methoxy-4-vinylphenol Keywords: Co-pyrolysis, Py-GC/MS dan coconut husk
Pelatihan Penggunaan Kit Detektif Kimia dalam Pembelajaran Kimia Bagi Guru-Guru SMA, MA dan SMK di Kalimantan Timur RR Dirgarini Julia Nurlianti Subagyono; Veliyana Londong Allo; Husna Syaima; Moh Syaiful Arif; Irfan Ashari Hiyahara; Nanang Tri Widodo; Rahmat Gunawan
AKM Vol 4 No 2 (2024): AKM : Aksi Kepada Masyarakat Jurnal Pengabdian Kepada Masyarakat - Januari 2024
Publisher : Sekolah Tinggi Ekonomi dan Bisnis Syariah (STEBIS) Indo Global Mandiri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36908/akm.v4i2.977

Abstract

Penggunaan media pembelajaran yang tepat dapat membantu guru kimia dalam menjelaskan konsep dan teori dalam ilmu kimia yang seringkali bersifat abstrak. Tim Qmiaku, Jurusan Kimia, FMIPA, Universitas Mulawarman mengembangkan Kit Detektif Kimia sebagai media pembelajaran baru, di mana siswa bermain peran sebagai detektif kimia. Pelatihan penggunaan Kit Detektif Kimia selanjutnya dilakukan dengan melibatkan mitra guru kimia di SMA, MA, dan SMK di Provinsi Kalimantan Timur. Kegiatan pengabdian masyarakat ini diberikan dengan metode pengenalan media pembelajaran, serta pelatihan dan pendampingan guru dalam menggunakan enam set percobaan pada Kit Detektif Kimia dengan materi asam basa, metode pemisahan sederhana, koloid, larutan dan suspensi, reaksi kimia, korosi, dan analisis kandungan bahan makanan sederhana. Berdasarkan hasil wawancara dan kuisioner yang diberikan, pelatihan ini mampu meningkatkan pemahaman dan kemampuan para guru dalam penggunaan Kit Detektif Kimia melalui penyampaian materi, diskusi/tanya jawab panduan penggunaan media yang mudah dipahami, dan pendampingan dari fasilitator pada praktik penggunaan media pembelajaran.
PYROLYSIS OF MERANTI SAWDUST (Shorea spp) WITH Ni/SBA-15 CATALYST USING PYROLYSIS GAS CHROMATOGRAPHY MASS-SPECTROMETRY (Py-GC/MS) Fitriah, Nur Azizah; Subagyono, R. R Dirgarini J.N.; Allo, Veliyana Londong
PROSIDING SEMINAR KIMIA Vol 2 No 1 (2023): Prosiding SNK 2023
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Pyrolysis of meranti sawdust (Shorea spp) with Ni/SBA-15 catalyst at 350°C, 450°C and 550°C using the pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC/MS) technique was carried out. This research was conducted to determine the pyrolysis product and the chemical composition of the pyrolysis product of meranti sawdust catalyzed by Ni/SBA-15 (20%wt.%). Based on the area percentage of products identified on the pyrogram, the chemical compositions of the pyrolysis product of meranti wood were 32.4%-43.6% products derived from cellulose/hemicellulose and 32.7%-23.3% products derived from lignin. The addition of Ni/SBA-15 catalyst to the pyrolysis of meranti sawdust increased the formation of cellulose/hemicellulose derivative products such as furan and furfural, as well as lignin derivative products such as vanillin. However, increasing the concentration of the catalyst also improved the amount of acetic acid, which is potentially corrosive and detrimental. Keywords: Pyrolysis, Meranti sawdust, Catalyst Ni/SBA-15, Py-GC/MS
A KINETIC STUDY OF PYROLYSIS OF BAGASSE USING THERMOGRAVIMETRIC ANALYSIS Rachmawanti, Octaviana; Subagyono, R.R. Dirgarini; Allo, Veliyana Londong
PROSIDING SEMINAR KIMIA Vol 2 No 1 (2023): Prosiding SNK 2023
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

A kinetic study of pyrolysis of bagasse using thermogravimetric analysis using the model-free methods, including the Kissinger-Akahira-Sunose (KAS) method and the Friedman method, has been carried out. The purpose of this study was to determine the pyrolysis decomposition process of bagasse and to determine the activation energy value of pyrolysis of bagasse. In this study, pyrolysis was carried out at various heating rates of 10, 15, 20, and 25 °C/minute using a Thermogravimetric Analyzer (TGA). The active pyrolysis temperature range of bagasse was + 104-431°C with a mass reduction of 56-64% where the decomposition process of cellulose, hemicellulose, and lignin in the biomass sample occurred. The activation energy obtained based on the KAS was 136.39 + 23.19 kJ/mol, wheres the activation energy obtained based on the Friedman method was 156.19 + 35.28 kJ/mol. Keywords: Bagasse, Pyrolysis, Thermogravimetry, Model-free, Activation Energy
PYROLYSIS OF BAGGASE WITH Ni/SBA-15 CATALYST USING PYROLYSIS GAS CHROMATOGRAPHY MASS-SPECTROMETER (Py-GC/MS) Praskianto, Ahmed Iqbal; Subagyono, R. R Dirgarini J.N.; Allo, Veliyana Londong
PROSIDING SEMINAR KIMIA Vol 2 No 1 (2023): Prosiding SNK 2023
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Pyrolysis experiments of bagasse with catalyst Ni/SBA-15 at 350°C, 450°C and 550°C using a Pyrolysis-Gas Chromatography-Mass Spectrometer (Py-GC/MS) been done. This study aims to determine the chemical composition of the pyrolysis product of bagasse with Ni/SBA catalysis (10% w/w). Based on the percent area value of the pyrolysis product identified on the pyrogram, the chemical composition of the pyrolysis product of bagasse produced was a cellulose/hemicellulose derivative product of 45.46%-60.24% and a lignin derivative product of 32.81%-17.77% . The addition of the catalyst Ni/SBA-15 to the pyrolysis of bagasse increased the amount of cellulose/hemicellulose derivative products such as ketones and furfural and then increased the amount of lignin derivative products such as vanillin and phenol. Keywords: Pyrolysis, Baggase, Catalyst Ni/SBA-15, Py-GC/MS
STUDI MOLECULAR DOCKING SENYAWA TURUNAN AURON SEBAGAI INHIBITOR GLIKOPROTEIN SPIKE SARS-COV-2 Allo, Veliyana Londong; Rahmah, Siti; Gunawan, Rahmat
Akta Kimia Indonesia Vol 8, No 2 (2023)
Publisher : LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j25493736.v8i2.16827

Abstract

The spike glycoprotein plays a role in binding and inserting viruses into host cells in the human body. Auron-derived natural compounds are believed to be potential inhibitors of spike glycoprotein. In this study, redocking of the native NAG ligand was carried out, as well as molecular docking of the 6VSB spike glycoprotein viral protein. The bond energy value for redocking the native NAG ligand is -6.2 kcal/mol, and the bond energy value for molecular docking of auron derivative compounds is -7.8 to -7.3 kcal/mol. Based on the bond energy value, the compound with potential as an inhibitor of spike glycoproteins is the 3',4, 4',6-tetrahydroxy auron compound. This is supported by the bond energy value and number of hydrogen bonds for this compound of -7.8 kcal/mol, forming four hydrogen bonds.
The Computational Calculation and Molecular Docking of Aeroplysinin-1 As Antibacterial Maahury, Mirella Fonda; Allo, Veliyana Londong
Indonesian Journal of Chemical Research Vol 9 No 2 (2021): Edition for September 2021
Publisher : Jurusan Kimia, Fakultas Sains dan Teknologi, Universitas Pattimura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30598/ijcr.2021.9-mir

Abstract

Aeroplysinin-1 is naturally found from marine sponges as an anti-bacterial compound. Computational calculation and molecular docking were performed for aeroplysinin. Aeroplysinin as an inhibitor has optimized in the gas phase using DFT with 6-31G(d) functional. The structure from geometry optimization of aeroplysinin-1is, not in one plane. The interaction of aeroplysinin-1 with two different DNA gyrase from E. Coli and S. Aureus. In this research,aeroplysinin-1 can inhibit the protein with the free binding energy of about -5.7 kcal/mol and -6.35 kcal/mol, respectively, for E. Coli and S. Aureus. The dominant molecular interaction is the hydrogen bond.
STUDI PIROLISIS MIKROALGA HIJAU (Spirulina platensis) TERHADAP KONSENTRASI PRODUK TURUNAN KLOROFIL Mardiani, Evi; Subagyono, RR Dirgarini Julia Nurlianti; Allo, Veliyana Londong
PROSIDING SEMINAR KIMIA Vol 3 No 1 (2024): Prosiding SNK 2024
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Pyrolysis study of green microalgae (Spirulina platensis) using Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC/MS) instrument has been conducted. In this study, the Spirulina platensis microalgae used had a moisture content of 8.34% and an ash content of 7.18%. Pyrolysis of Spirulina platensis microalgae at 450˚C produced chlorophyll derivative products of 6.20%. Keywords : Spirulina platensis, pyrolysis, Py/GC-MS
A MINI REVIEW: STUDI KOMPUTASI TERHADAP STRUKTUR ELEKTROLIT PADA SILICENE, GRAPHENE, DAN GERMANENE Harvina, Harvina; Gunawan, Rahmat; Allo, Veliyana Londong
PROSIDING SEMINAR KIMIA Vol 3 No 1 (2024): Prosiding SNK 2024
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

Research on two-dimensional (2D) materials such as graphene, silicene, and germanene has garnered significant attention due to their unique electronic and mechanical properties. This mini review employs Density Functional Theory (DFT) to compare the electronic properties of these three materials. The results show that graphene, with sp² hybridization, possesses outstanding electrical conductivity and high mechanical strength, with a lattice constant of 2.46 Å. Silicene and germanene, composed of silicon and germanium atoms respectively, exhibit higher surface reactivity and potential for advanced electronic applications due to their ability to open band gaps through various methods. Silicene has a lattice constant of 3.90 Å and an electronegativity of 1.9, while germanene has a lattice constant of 3.97 Å and an electronegativity of 2.01. The band structures of silicene and graphene do not exhibit band gaps, with dominant states in the p orbital, whereas germanene displays semiconductor behavior with a zero band gap opening at the K-point. Graphene shows high in-plane stiffness, while silicene and germanene have respective stiffness, with graphene and silicene being brittle and germanene being ductile. This study provides insights into the fundamental differences in the electronic properties of graphene, silicene, and germanene, as well as their potential applications in semiconductor technology and high-speed, low-energy electronic devices. Keywords: Silicene, Graphene, Germanene, DFT, Electronic structure
ANALISIS TERMOGRAVIMETRI Spirulina platensis DENGAN KATALIS Ni/Al-SBA-15 RASIO Si/Al=10 MENGGUNAKAN LAJU PEMANASAN 10°C/MENIT Anisa, Nia Nur; Subagyono, R.R. Dirgarini Julia Nurlianti; Allo, Veliyana Londong
PROSIDING SEMINAR KIMIA Vol 3 No 1 (2024): Prosiding SNK 2024
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

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Abstract

The thermogravimetric analysis of Spirulina platensis with Ni/Al-SBA-15 catalyst (Si/Al ratio = 10) using a heating rate of 10°C/min has been conducted. This study was performed to determine and analyze the chemical decomposition process of Spirulina platensis with a pyrolysis heating rate of 10°C/min. Based on the characterization results, Spirulina platensis has a moisture content of 8.34% and an ash content of 7.18%. The TG and DTG curves show the active pyrolysis temperature range of Spirulina platensis microalgae with Ni/Al-SBA-15 catalyst between approximately 155-496°C. The chemical decomposition of Spirulina platensis with Ni/Al-SBA-15 catalyst occurs in three stages: 1. water evaporation, 2. active pyrolysis, where the decomposition of carbohydrate, protein, and lipid compounds takes place, and 3. passive pyrolysis caused by gasification and the formation of non-volatile carbon compounds that vaporize to form CO and CO2 gases at high temperatures. Keywords: Thermogravimetry, Spirulina platensis, Pyrolysis, Ni/Al-SBA-15
Co-Authors Anisa, Nia Nur D J N Subagyono Digva Willyan Djihan Ryn Pratiwi Evi Mardiani, Evi Fitriah, Nur Azizah Gunawan, Rahmat Halimatus Sa'diyah Harvina, Harvina Husna Syaima Irfan Ashari Hiyahara Irfan Ashari Hiyahara Maahury, Mirella Fonda Manawan, Maykel Moh Syaiful Arif Muhammad Abdulkadir Martoprawiro Muhammad Irvan Mulya Pratama Nana Lestari Nanang Tri Widodo Noor Afdaliah Noor Hindryawati Praskianto, Ahmed Iqbal Putri, Dini Hariyanto R R Dirgarini Julia Nurlianti Subagyono Rachmawanti, Octaviana Rahmah, Siti Rahmat Gunawan RAHMAT GUNAWAN Rahmat GUnawan Rahmat Gunawan RR Dirgarini Julia Nurlianti Subagyono RR Dirgarini Julia Nurlianti Subagyono Rudy Agung Nugroho Siti Sarah Subagyono, R. R Dirgarini J.N. Subagyono, R.R. Dirgarini Subagyono, R.R. Dirgarini Julia Nurlianti Subagyono, RR Dirgarini Julia Nurlianti Wardina Masdalifa