Article Per Year (5 Year)
p-Index From 2021 - 2026
0.23
P-Index
This Author published in this journals
All Journal ROTOR: JURNAL ILMIAH TEKNIK MESIN SAINSTEK
Adjar Pratoto
Unknown Affiliation
Automotive Engineering Civil Engineering, Building, Construction & Architecture Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
PENGARUH LAMA WAKTU PENGGETARAN ULTRASONIC BATH TERHADAP SIFAT MEKANIK DAN MORFOLOGI PATAHAN BIOKOMPOSIT PATI TAPIOKA/SERAT RAMI (BOEHMERIA NIVEA) Mochamad Asrofi; Hairul Abral; Anwar Kasim; Adjar Pratoto; Herwin Gevin; Melbi Mahardika
ROTOR Vol 10 No 2 (2017)
Publisher : Jurusan Teknik Mesin Fakultas Teknik Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (266.748 KB) | DOI: 10.19184/rotor.v10i2.5574

Abstract

This study reported about mechanical properties and fracture surface of ramie fiber reinforced tapioca starch based biocomposites. The amount of fibers in matrix was kept constant at 10% from dry weight starch basis. Fabrication of biocomposites was solution casting. The effect of vibration duration from ultrasonic bath was 0, 15, 30, and 45 min. This treatment was applied to biocomposites while gelatinized. Tensile test was carried out to determine the mechanical properties of biocomposites. Fracture surface of biocomposites after tensile test was observed by using scanning electron microscopy (SEM). The result shows that, tensile strength increased when vibration time was added. The maximum tensile strength was obtained at 45 min vibration time with 2,84 MPa. This phenomenon was supported by SEM observation which indicate compact structure. Keywords: Tapioca starch, ramie fiber, biocomposites, mechanical properties, SEM
Model Persamaan Matematik Isoterm Sorpsi untuk Kayu Manis (Cinnamomum burmannii) Habibullah, Habibullah; Adjar Pratoto
SAINSTEK Vol. 13 No. 2 (2025)
Publisher : Sekolah Tinggi Teknologi Pekanbaru

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35583/js.v13i2.360

Abstract

Penelitian ini bertujuan untuk mengembangkan model matematik isoterm sorpsi (adsorpsi dan desorpsi) untuk kayu manis (Cinnamomum burmannii) pada suhu 30?±1°C dari data empirik yang diperoleh dengan menggunakan metode gravimetri statis. Kelembapan relatif udara sekeliling diatur dengan menggunakan campuran larutan H?SO? dan akuades dalam rentang kelembapan relatif (RH) atau aktifitas udara antara 16% hingga 98%. Pengujian, kadar air kesetimbangan dilakukan dalam dua arah, yaitu adsorpsi dan desorpsi. Untuk adsorpsi, sampel dikeringkan terlebih dahulu dengan metode oven sebelum dimasukkan ke dalam bejana kedap udara dengan kelembaban udara yang telah dikondisikan. Sedangkan untuk proses desorpsi, sampel direndam dalam akuades terlebih dahulu.. Hubungan antara kadar air kesetimbangan dan kelembapan relatif menunjukkan kurva sigmoid khas tipe II menurut klasifikasi Brunauer. Dalam pemodelan matematik, digunakan lima model isoterm sorpsi, yaitu GAB, Henderson, Oswin, Peleg, dan Smith. Evaluasi fitness model matematik dilakukan dengan menggunakan parameter statistik RMSE, ?², modulus error, dan koefisien determinasi (R²). Hasil menunjukkan bahwa model GAB paling sesuai untuk data adsorpsi, sedangkan model Smith memberikan hasil terbaik untuk desorpsi.
Co-Authors Abral, Hairul Anwar Kasim Habibullah Habibullah Herwin Gevin Melbi Mahardika Mochamad Asrofi