Judul: Analysis of Effect Addition Oxygen at Intake Suction on the Performance Engine Diesel on Two-Wheeled Tractor
Abstrak: Motor diesel memiliki daya dan efisiensi termal yang besar. Namun dalam penggunaannya masih terdapat masalah pembakaran yang kurang sempurna sehingga mengakibatkan daya berkurang dan konsumsi bahan bakar meningkat. Di satu sisi, produksi minyak bumi di Indonesia menurun setiap tahunnya. Oksigen berperan penting dalam pembakaran serta meningkatkan stabilitas pembakaran sempurna terjadi. Oleh karena itu, penelitian bertujuan menguji dan membandingkan kinerja motor diesel dengan penambahan oksigen pada udara intake. Penggunaan oksigen konsentrator sebagai penambah oksigen dalam penelitian ini. Penelitian dilakukan dengan dua perlakuan, kondisi normal dan penambahan oksigen. Variasi penambahan oksigen terdiri dari 1 lpm, 3 lpm, dan 5 lpm. Pengujian dilakukan tiga kali pengulangan pada setiap perlakuan. Parameter penelitian terdiri dari torsi, daya, rpm, laju konsumsi, dan sfc. Hasil penelitian membuktikan adanya pengaruh penambahan oksigen terhadap kinerja motor diesel traktor roda dua. Torsi meningkat 15% dari 1019,2 Nm menjadi 1176 Nm, Daya maksimum meningkat 16% dari 4,20 kW menjadi 4,87 kW, sedangkan sfc minimum menurun 18% dari 450,85 gr/kW-h menjadi 369,5 gr/kW-h. Kata kunci: Motor diesel, Penambahan Oksigen, Kinerja, Diesel engines have great power and thermal efficiency. However, in used there is still the problem of incomplete combustion resulting in reduced power and increased fuel consumption. On the one hand, crude oil production in Indonesia is declining every year. Oxygen plays an important thing in combustion and increases the stability of complete combustion occurs. Therefore, this research aims to test and compare the performance of diesel engines with addition oxygen in the intake air. Oxygen concentrator as an addition oxygen in the research. The research was conducted with two treatments, normal conditions and addition oxygen. Variation addition oxygen consists of 1 lpm, 3 lpm, and 5 lpm. The test was repeated three times for each treatment. The research parameters consist of torque, power, rpm, consumption rate, and sfc. The results proved the effect adding oxygen to performance of two-wheeled tractor diesel engine. Torque increased by 15% from 1019,2 Nm to 1176 Nm, maximum power increased by 16% from 4,20 kW to 4,87 kW, while minimum sfc decreased by 18% from 450,85 gr/kW-h to 369,5 gr/kW h. Keywords: Engine diesel, Addition Oxygen, Performance
Keyword: engine diesel, performance, addition oxygen, performansi, penambahan oksigen, motor diesel

Judul: Analysis of the Addition of Ultra Fine Bubble in Fuel Variations on Two Wheel Tractor Diesel Engine Exhaust Emission
Abstrak: Sektor pertanian merupakan salah satu sektor yang memberi dampak positif bagi pertumbuhan ekonomi. Sebagian besar alat dan mesin pertanian menggunakan enjin diesel sebagai sumber penggerak. Sementara itu gas buang yang dihasilkan oleh enjin diesel sangat berbahaya bagi kesehatan manusia. Sehingga diperlukan inovasi yang dapat menurunkan kadar emisi enjin diesel pada sektor pertanian. Teknologi ultra fine bubble (UFB) yang berkembang saat ini mampu memperkaya oksigen yang ada pada bahan bakar dan berpotensi mengurangi emisi gas buang. Penelitian ini dilakukan guna menganalisa emisi gas buang pada variasi bahan bakar normal dan ber-UFB, serta membandingkan hasil emisi dengan standar yang berlaku. Metode yang dilakukan ialah pengumpulan data hasil pengujian berbasis eksperimen. Hasil yang diperoleh ialah persentase penurunan emisi tertinggi dari bahan bakar normal ke bahan bakar ber-UFB terjadi pada bahan bakar B30. Secara keseluruhan UFB mampu menurunkan emisi terutama pada kandungan nitrogen monoksida (NO), sulfur dioksida (SO2) dan nitrogen oksida (NOx). Pada standar baku mutu emisi pembangkit listrik tenaga diesel, seluruh variasi bahan bakar sudah memenuhi standar kandungan SO2. Sementara itu B30 normal belum memenuhi standar kandungan NOx, dan Pertamina Dex normal, B30 normal, B30 ber-UFB belum memenuhi standar karbon monoksida (CO). Pada standar baku mutu Euro 2 dan Euro 4, seluruh variasi bahan bakar memenuhi standar kandungan CO dan NOx., The agricultural sector is one sector that has a positive impact on economic growth. Most of the tools and agricultural machinery use diesel engines as a source of propulsion. Meanwhile, the exhaust gas produced by diesel engines is very dangerous for human health. So innovation is needed that can reduce diesel engine emission levels in the agricultural sector. Ultra fine bubble technology which is currently developing is capable of enriching the oxygen in the fuel and potentially reducing exhaust gas emissions. This research was conducted to analyze exhaust gas emissions on normal and UFB fuel variations, as well as compare the emission results with the applicable standards. The method used is data collection based on experimental testing. The result obtained is the highest emission reduction percentage from normal fuel to fuel with UFB occurs in B30 fuel. Overall UFB is capable of reducing emissions, especially in the content of nitrogen monoxide (NO), sulfur dioxide (SO2) and nitrogen oxide (NOx). In the emission quality standards for diesel power plants, all types of fuel meet SO2 content standards. Meanwhile normal B30 does not meet NOx content standards, and normal Pertamina Dex, normal B30, UFB B30 does not meet carbon monoxide (CO) standards. In Euro 2 and Euro 4 quality standards, all fuel variations meet CO and NOx content standards.
Keyword: Bahan Bakar, Enjin Diesel, Emisi Gas Buang, Ultra Fine Bubble, Diesel Engine, Exhaust Gas Emission, Fuel, Ultra Fine Bubble

Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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