Article Per Year (5 Year)
p-Index From 2020 - 2025
1.376
P-Index
This Author published in this journals
All Journal IPTEK Journal of Proceedings Series Jurnal Fisika Unand JFA (Jurnal Fisika dan Aplikasinya) JPSE (Journal of Physical Science and Engineering) Journal of Physics: Theories and Applications Jurnal Pengabdian Ilung (Inovasi Lahan Basah Unggul) Sewagati
Astuti, Fahmi
Institut Teknologi Sepuluh Nopember
Agriculture, Biological Sciences & Forestry Arts Humanities Astronomy Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Dentistry Earth & Planetary Sciences Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Languange, Linguistic, Communication & Media Law, Crime, Criminology & Criminal Justice Materials Science & Nanotechnology Mathematics Medicine & Pharmacology Nursing Physics Public Health Social Sciences Other

Published : 9 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 9 Documents
Search

 1 
Study of Morphology of Film Reduced Graphene Oxide from Coconut Shell Mas’udah, Kusuma Wardhani; Astuti, Fahmi; Darminto, Darminto
IPTEK Journal of Proceedings Series No 1 (2015): 1st International Seminar on Science and Technology (ISST) 2015
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j23546026.y2015i1.1201

Abstract

Coconut shell as the main ingredient in this study were converted into charcoal. The resulted sample coconut shell charcoal was used as a powder and heated. After heating, the powder was dissolved into distilled water. They were coated on the glass substrates using a spin-coating method. Furthermore, this study characterizations using Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) were conducted for all samples. r-GO layer coconut shell has been successfully made on glass substrates, is shown with layers that have accumulated weight percentage of carbon atoms in each sample layer, that is equal to 84.55% and 20.61%.
Study of the formation of amorphous carbon and rGO-like phases from palmyra sugar by variation of calcination temperature Fahmi Astuti; Novita Sari; Vera Laviara Maghfirohtuzzoimah; Retno Asih; Malik Anjelh Baqiya; Darminto Darminto
Jurnal Fisika dan Aplikasinya Vol 16, No 2 (2020)
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat, LPPM-ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j24604682.v16i2.6706

Abstract

We have processed biomass from palmyra sugar to produce allotrope carbon by heating process with the variation of calcination temperature. The formation of amorphous carbon (a-C) was confirmed from the XRD result heated at 400°C with the observation of the peak at the position of ~24o. By increasing the temperature at 700°C, the presence of two peaks at 24o and 43o were observed, indicating the formation of rGO-like phase. The functional groups detected by FTIR spectra consist of C=C, C-O, C=O, C-H and O-H. The result of conductivity measurement exhibits that the material can be classified as semiconducting materials.
Study on Physical Properties of Reduced Graphene Oxide from Heating Coconut Shell Mas’udah Kusuma Wardhani; Fahmi Astuti; Darminto Darminto
JPSE (Journal of Physical Science and Engineering) Vol 1, No 1 (2016): JPSE (Journal of Physical Science and Engineering)
Publisher : Universitas Negeri Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (864.023 KB)

Abstract

A research to determine the solar activity in the months from January to March 2015, and analyze the characteristics of flare on the rotation angle shifting of the sunspot group of sunspot sample observed, has been conducted. The method was observation and descriptive analysis of quantitative data. Determination of coordinates of sunspot was done using the software IDL. These observations were made in the Aerospace Observation Center (BPD) LAPAN Watukosek. Data were analyzed in the form of a sketch-owned BPD Sunspot LAPAN Watukosek, ie sunspot sketch of months from January to March in 2015 and the data was taken from NOAA. The results showed that the flare is not always the case in large class of sunspot groups, however, the small class was able to produce a flare. Most flares ware occur after experiencing a shift angle in the preceding or following although with angles that were not too large (<10 °). The highest solar activity was occurred in January 2015 with the appearance of a sunspot group consisting of as many as 130 in 1063 sunspots. DOI: 10.17977/um024v1i12016p001
Physical Properties Comparison of rGO-like phase prepared from Coconut Shell and the Commercial Product Retno Asih; Maya Mahirotul Septya; Erik Bhekti Yutomo; Fahmi Astuti; Malik Anjelh Baqiya; Darminto Darminto
Jurnal Fisika dan Aplikasinya Vol 16, No 2 (2020)
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat, LPPM-ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12962/j24604682.v16i2.6712

Abstract

Physical properties of reduced graphene oxide (rGO) prepared from two different raw materials, namely coconut shell (rGO-s) and graphite mineral (rGO-c, produced by Graphenea Inc.), have been investigated. While both samples have the same density of about 1.9 g/cm3, rGO-c has more porous of about 1.3 cc/g with diameter of 10.8 nm compared to rGO-s which has 0.2 cc/g porous with diameter of 2.4 nm. Specific surface area in rGO-c was also obtained much larger than that of rGO-s. rGO-c and rGO-s have specific surface area of ~298 m2/g and ~475 m2/g, respectively. Examinations on particle size and surface morphology show that rGO-c has homogenous particles which consist of transparent thin sheets, while rGO-s has rather heterogenous particles that look like dens stacked sheets. The presence of C and O was confirmed at the observed morphology. The difference in physical features were then found to influence the obtained electrical conductivity of the samples. rGO-c has higher conductivity than rGO-s. Estimation on gap energy (Eg) indicates that rGO-c and rGO-s have Eg in the range of semiconducting materials. The study provides a better understanding on physical properties of coconut shell-derived rGO to further revise synthesis method to improve quality of the obtained rGO.
Oxidation state analysis of LiFeSixP1-xO4/C (x = 0.06) with X-ray absorption near edge structure (XANES) in Fe K-edge and Si K-edge Sahara Hamas Intifadhah; Vera Laviara Maghfirohtuzzoimah; Pelangi Az-zahra; Wantana Klysubun; Fahmi Astuti; Mochamad Zainuri; Darminto Darminto
Journal of Physics: Theories and Applications Vol 5, No 1 (2021): Journal of Physics: Theories and Applications
Publisher : Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/jphystheor-appl.v5i1.51855

Abstract

The development of LiFePO4 as a cathode materials on lithium-ion battery was increased with the use of additional techniques such as atomic doping and coating. The material used in this report was LiFeSi0.06P0.94O4/C (LFP Si-6%), synthesized with doping silicon 6% and 11wt% carbon coating by a solid state method. X-ray Absorption Spectroscopy (XAS) characterization was used to investigate the effect on electronic and atomic structure of LFP Si-6%, especially in X-ray Absorption Near Edge Strucuture (XANES) region. XANES data measured on Fe K-edge and Si K-edge. Fe foil, FeO, Fe2O3, FePO4, Si powder, SiO, SiO2 were used as a standard sample for comparison with the result of LFP Si-6%. XANES analysis showed that the energy absorption of Fe K-edge and Si K-edge in LFP Si-6% was 7124.94 eV and 1846.16 eV, respectively. The oxidation state of Fe was Fe2.576+ between Fe2+ and Fe3+, while Si was close to the estimation of Si4+. In addition, the linear combination fitting (LCF) in XANES Fe K-edge was performed to show the ratio of Fe2+/Fe3+ (FeO/Fe2O3).
Pemanfaatan Arang Batok Kelapa Sebagai Media Filter Air Untuk Media Pembelajaran di Jombang Linda Silvia; Fahmi Astuti; Sri Yani Purwaningsih; Yoyok Cahyono; Agus Purwanto; Darminto Darminto; Mochamad Zainuri
Jurnal Pengabdian ILUNG (Inovasi Lahan Basah Unggul) Vol 2, No 2 (2022)
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/ilung.v2i2.5871

Abstract

Pada umumnya pelajaran fisika dianggap sebagai pelajaran yang tidak mudah oleh kebanyakan siswa. Walaupun sebagaimana kita ketahui pemanfaatan ilmu fisika sangat banyak dalam kehidupan nyata. Salah satunya penggunaan arang batok kelapa sebagai media filter air. Salah satu tujuan kegiatan abdimas ini agar siswa mampu dan memahami pengaplikasian pelajaran fisika dalam kehidupan sehari-hari dan guru juga memiliki strategi pembelajaran berbasis aplikasi untuk membuat siswanya tertarik terhadap mata pelajaran fisika dengan memanfaatkan bahan yang tersedia di alam cukup melimpah dan harga murah. seperti arang batok kelapa. SMA A Wahid Hasyim Tebuireng Jombang mempunyai jumlah siswa yang cukup banyak yang berasal dari berbagai macam daerah di Jombang sebagai sasaran diharapkan dapat memberikan manfaat untuk mengaplikasikan teknologi filter air di daerahnya dan membagi pengetahuan kepada teman atau masyarakat disekitarnya terutama daerah yang rawan air bersih. Berdasarkan kegiatan pengabdian kepada masyarakat menunjukkan bahwa siswa dan guru sangat antusias mengikuti kegiatan dan hasil filter air berbasis arang batok kelapa mampu meningkatkan kualitas air sekitar 50% yang dapat digunakan sebagai media pembelajaran.
Pemanfaatan Karbon Aktif Tempurung Kelapa sebagai Media Filtrasi Air di Desa Sumberwudi Lamongan Linda Silvia; Darminto; Agus Purwanto; Fahmi Astuti; Mochamad Zainuri
Sewagati Vol 5 No 2 (2021)
Publisher : Pusat Publikasi ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1292.992 KB)

Abstract

Ketersediaan air bersih di wilayah pedesaan dan pinggiran sungai sangat tergantung pada sumber air di alam seperti sumur air tanah dangkal. Namun, ketika musim kemarau, sumur air tanah dangkal menjadi payau dan membuat masyarakat Desa Sumberwudi Karanggeneng Lamongan beralih memanfaatkan aliran air dari Sungai Bengawan Solo. Pengolahan air sudah dilakukan menggunakan metode pengendapan sederhana, namun seringkali air yang dihasilkan masih jauh dari kata jernih dan bersih karena masih banyaknya endapan lumpur yang terbawa sehingga berwarna kecoklatan. Sehingga dalam program pengabdian masyarakat ini akan dibuat alih teknologi dengan memanfaatkan karbon aktif tempurung kelapa yang keberadaannya melimpah di alam dengan harga yang cukup terjangkau sebagai media fitrasi air. Filter yang dibuat dipasang di salah satu fasilitas umum (mushola) dan SMPN 1 Karanggeneng Lamongan. Berdasarkan hasil pengujian air menggunakan water quality tester yang telah diperoleh bahwa filter air mampu meningkatkan kualitas air sebesar 25%. Pengujian yang digunakan antara lain: Total Dissolved Solid (TDS), pH, salinitas, elektrokonduktivitas, dan temperatur. Dengan adanya kegiatan ini diharapkan masyarakat dapat membuat filter air secara mandiri menggunakan bahan di sekitar dengan harga yang cukup terjangkau untuk mendapatkan kualitas air yang memadai.
Pengolahan Limbah Sabut Kelapa Menggunakan Mesin Pencacah dalam Upaya Pemanfaatannya sebagai Produk Tepat Guna di Desa Candimulyo - Dolopo - Madiun Fahmi Astuti; Suminar Pratapa; Suasmoro; Triwikantoro; Yoyok Cahyono
Sewagati Vol 7 No 3 (2023)
Publisher : Pusat Publikasi ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1994.73 KB) | DOI: 10.12962/j26139960.v7i3.504

Abstract

Produksi buah kelapa Indonesia rata-rata 15,5 miliar butir/tahun, setara 3,02 juta ton kopra, 3,75 juta ton air, 0,75 juta ton arang tempurung, 1,8 juta ton serat sabut, dan 3,3 juta ton debu sabut. Sabut kelapa merupakan hasil samping dari buah kelapa yang berpotensi cukup besar. Saat ini pemanfaatannya masih belum optimal bahkan cenderung menjadi limbah lingkungan. Pemanfaatan mesin pencacah untuk pengolahan lebih lanjut sabut kelapa menjadi produk tepat guna misalnya: serat sabut kelapa (cocofiber) dan serbuk sabut kelapa (cocopeat) yang merupakan dua produk turunan dari sabut kelapa yang melalui beberapa penelitian dapat diolah menjadi material pendukung interior dan furnitur. Dengan demikian, maka limbah sabut kelapa dapat menjadi lebih bernilai ekonomis yang tentunya sangat berdampak positif pada masyarakat yang tinggal di sekitar lokasi penghasil kelapa. Sasaran masyarakat dalam kegiatan ini adalah masyarakat Desa Candimulyo, Dolopo, Madiun yang mana terdapat pengepul kelapa dan sentra distribusi kelapa di desa tersebut. Produk mesin pencacah yang dibuat bekerjasama dengan industri diharapkan menjadi produk dari perguruan tinggi yang dapat diimplementasikan langsung dan bermanfaat dalam jangka panjang untuk mitra.
X-ray Absorption Near Edge Structure (XANES) Spectrum Interpretation for LiFePO4-Silicon Doped Cathode Material Sahara Hamas Intifadhah; Kholis Nurhanafi; Fahmi Astuti; Rahmawati Munir; Dadan Hamdani; Darminto Darminto
Jurnal Fisika Unand Vol 12 No 3 (2023)
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jfu.12.3.348-354.2023

Abstract

LiFePO4-Silicon doped has been widely developed as a battery cathode material. Due to the doping of silicon atoms, this study aims to determine the peak energy (E0), oxidation state and percentage of component composition for Fe K-edge. The experimental sample used are LFP Si-0%, LFP Si-1%, LFP Si-3% and LFP Si-6%. These samples were characterized using XAS (X-ray Absorption Spectroscopy). XANES spectrum showed the peak energy of Pre-edge area is 7113.08 – 7114.49 eV. The oxidation state of Fe atoms were increased and tend to be Fe3+ than Fe2+. Moreover, Linear Combination Fitting (LCF) used to determine the ratio composition FeO/Fe2O3 in experimental samples. The ratio composition indicated Fe atom is multivalent, when the percentage of silicon-doped increases, the ratio of Fe3+ increased.It has been found that the presence of silicon atoms in the LiFePO4 structure has an effect in electronic structure.
Co-Authors Agus Purwanto Agus Purwanto Cahyono, Yoyok Dadan Hamdani Darminto Darminto Darminto Darminto Darminto Darminto Darminto Darminto Darminto Darminto, Darminto Erik Bhekti Yutomo Intifadhah, Sahara Hamas Kholis Nurhanafi Linda Silvia, Linda Malik Anjelh Baqiya Mas’udah, Kusuma Wardhani Mas’udah Kusuma Wardhani Maya Mahirotul Septya Munir, Rahmawati Novita Sari Pelangi Az-zahra Retno Asih Sriyani Purwaningsih Suasmoro Suasmoro Suminar Pratapa Triwikantoro Triwikantoro Vera Laviara Maghfirohtuzzoimah Vera Laviara Maghfirohtuzzoimah Wantana Klysubun Zainuri (DOI: 10.12962/j24604682.v12i2.1331), Mochamad