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Filler Composition Effects on Tensile Strength And Composite Material Toughness of Rice-Resin Husk Powder Istiroyah Istiroyah; L. Nuriyah; Retnowati Retnowati
Natural B, Journal of Health and Environmental Sciences Vol 1, No 4 (2012)
Publisher : Natural B, Journal of Health and Environmental Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (10.193 KB) | DOI: 10.21776/ub.natural-b.2012.001.04.8

Abstract

The rice husk flour- resincomposite has been made. This research aims to make the rice husk flour - resin composite and analyze the effect of filler composition to their tensile strength and toughness. The filler composition used is 0%, 10%, 20%, 30, 40%, 50% dan 60%. The Results of tensile test show that the best tensile strength is 113.02 ±11.60 MPa for polystiren sample. The best toughness with impact test is 47.92±0,36 KJ/m2 for 30% filler with polyester resin.
Effects of Adhesives on Quality Biomass Briquette Abdurrouf Abdurrouf; Istiroyah Istiroyah; Gancang Saroja
Natural B, Journal of Health and Environmental Sciences Vol 1, No 1 (2011)
Publisher : Natural B, Journal of Health and Environmental Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (559.209 KB) | DOI: 10.21776/ub.natural-b.2011.001.01.1

Abstract

Production of briquettes from organic waste with starch as an adhesive, has been done. The briquette's quality is improved by (i)  the milling of organic waste is conducted in dry phase, and (ii) the mixing between organic waste and starch as an adhesive is carried out on raw phase. This study shows that the best briquette was obtained when the ratio of organic wastes - starch was 10:3. In such composition, mass of the produced briquette was more than 50% of the mass of organic waste. For more improvement, it is necessary to find a better pressing and drying technique. It is also need to make briquette in large numbers to improve its characterization.
Studi Kelajuan Elektrolit Terhadap Kapasitas Baterai Dinamis Asam Timbal Sel Tunggal Muhammad Ghufron; Istiroyah Istiroyah; Cholisina A. Perwita; Levinus Gobay; Fakhrusy Rizki Ramadhan; Kurriawan Budi Pranata
Prosiding SNFA (Seminar Nasional Fisika dan Aplikasinya) 2020: Prosiding SNFA (Seminar Nasional Fisika dan Aplikasinya) 2020
Publisher : Universitas Sebelas Maret

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/prosidingsnfa.v5i0.46605

Abstract

Abstract: Electrolyte flow rate is one of the important parameters on Redox Flow Battery (RFB) performance. A single cell lead acid battery has been made with the RFB system by giving 4 variations in flow speed (45 mL/min, 77 mL/min, 90 mL/min and 105 mL/min), two electrolyte concentrations (30% and 40%) and applied 1 A of charging-discharging current with the aim of an88ukmalyzing the relationship of the electrolyte flow rate of the battery to the RFB system capacity. The results showed that the flow of electrolytes from tanks outside the cell battery was able to increase battery capacity by increasing the number of spontaneous redox reactions during charging and discharging. The cycle time and battery capacity increase at the beginning of the filling-emptying cycle but have a downward trend with the increasing number of cycles. Batteries with an electrolyte concentration of 30% and speeds of 90 mL/mnt have the best performance in terms of discharging capacity compared to other batteries.Abstrak: Laju aliran elektrolit adalah salah satu parameter penting pada kinerja Redox Flow Battery (RFB). Baterai asam timbal sel tunggal telah dibuat dengan sistem RFB dengan memberikan 4 variasi kelajuan aliran (45 mL/mnt, 77 mL/mnt, 90 mL/mnt dan 105 mL/mnt), dua konsentrasi elektrolit (30% dan 40 %) dan diterapkan 1 A arus pengisian-pemakaian dengan tujuan menganalisis hubungan laju aliran elektrolit baterai dengan kapasitas sistem RFB. Hasil penelitian menunjukkan bahwa aliran elektrolit dari tangki di luar baterai sel mampu meningkatkan kapasitas baterai dengan meningkatkan jumlah reaksi redoks spontan selama pengisian dan pemakaian. Waktu siklus dan kapasitas baterai meningkat pada awal siklus pengisian-pengosongan tetapi memiliki tren menurun dengan meningkatnya jumlah siklus. Baterai dengan konsentrasi elektrolit 30% dan kelajuan 90 mL/mnt memiliki kinerja terbaik dalam hal kapasitas pemakaian dibandingkan baterai lainnya.
Pengerasan Baja AISI 316L Menggunakan Metode Pack Carburizing Bersumber Karbon Kayu Mahoni muhammad ghufron; Istiroyah Istiroyah; Rena Wahju Dhiaul In’am
SPECTA Journal of Technology Vol. 5 No. 2 (2021): SPECTA Journal of Technology
Publisher : LPPM ITK

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (600.809 KB) | DOI: 10.35718/specta.v5i2.361

Abstract

Peningkatan kekerasan paduan baja dapat dilakukan dengan meningkatkan kandungan karbon dipermukaanya. Baja AISI 316 L yang memiliki kekerasan awal 189 HV300 dapat ditingkatkan kekerasannya melalui peningkatan jumlah karbon dipermukaan dengan metode pack carburizing. Pada penelitian ini kayu mahoni digunakan sebagai sumber karbon aktif yang diperoleh dengan pemanasan dan pengayakan 150 mesh. Pack carburizing dilakukan pada suhu tinggi yakni 700oC, 750oC, 800oC dan 850oC selama 8 dan 16 jam yang kemudian dilakukan uji kekerasan menggunakan micro vickers hardness tester. Semua spesimen hasil pack carburizing mengalami kenaikan kekerasan dibandingkan dengan spesimen tanpa perlakuan dengan range kenaikan sebesar 24-367 HV3. Kekerasan tertinggi diperoleh pada pemanasan selama 16 jam pada suhu 700oC. Hasil pengujian sudut kontak menunjukkan adanya perubahan sifat pada permukaan dari hidrofilik ke hidrofobik untuk semua sampel sementara dari hasil mikroskop optik diperoleh distribusi ukuran butir kurang dari 60 µm dengan dominan range 15-25 µm.