Judul: Effect of Addition of Essential Oil Bio-additive to B30 Biodiesel Fuel on Diesel Engine Performance
Abstrak: Biosolar B30 adalah campuran bahan bakar solar dan biodiesel dengan perbandingan 70:30. Permasalahan penggunaan biodiesel meliputi tingginya partikulat, kadar air dan penurunan masa pakai filter sehingga perlu adanya bahan tambahan untuk menangani permasalahan tersebut dengan menambahkan bioaditif. Penelitian bertujuan mengetahui pengaruh penambahan bioaditif dilihat dari karakteristik B30, performa, emisi gas buang mesin diesel dan menentukan formula terbaik dari dua jenis formula yaitu bioaditif A (campuran minyak terpentin, clove terpene, sereh wangi) dan bioaditif B (campuran minyak terpentin, clove terpene, rhodinol). Pengolahan data menggunakan metode deskriptif dan one-way anova pada taraf 95% dilanjut menggunakan uji Least Significance Different. Uji karakterisasi menganalisis beberapa parameter, seperti viskositas, densitas, titik nyala, nilai kalor, kadar air dan partikulat yang telah memenuhi Keputusan Direktur Jenderal Minyak dan Gas Bumi 234.K/10/DJM.S Tahun 2019. Uji performa menganalisis beberapa parameter, seperti nilai torsi dan daya yang mengalami kenaikan sebesar 0,1 – 5% pada bioaditif B dan konsumsi bahan bakar mengalami kenaikan pada bioaditif A dan bioaditif B. Sedangkan parameter pada uji emisi meliputi CO2, NOx, dan Smoke. Nilai emisi NOx dan CO2 lebih rendah dengan menggunakan bioaditif B dan emisi smoke terjadi peningkatan pada bioaditif B., Bio solar B30 is a mixture of diesel fuel and biodiesel with a ratio of 70:30. The problems of using biodiesel, such as high particulates, water content, and decreased duration of the filter so that additional materials are needed to deal with these problems by adding bioadditives. This study aims to determine the effect of adding bio-additives seen from the characteristics of B30, performance, diesel engine exhaust emissions and determine the best formula from two types of formulas, namely bioadditive A (a mixture of turpentine oil, clove terpenes, citronella), and bioadditive B (a mixture of turpentine oil, clove terpenes, rhodinol). Data processing used descriptive methods and one-way ANOVA at the 95% confidence level followed by the Least Significance Different test. The characterization test analyzes several parameters, such as viscosity, density, flash point, calorific value, water content, and particulates, and has complied with the Director-General of Oil and Gas Decree of 234.K/10/DJM.S Year 2019. The performance test analyzed several parameters, such as the torque and power values which increased by 0.1 – 5% in the bio-additive B and fuel consumption increased in bio-additive A and bio-additive B. Meanwhile, the parameters in the emission test included CO2, NOx, and Smoke. The value of NOx and CO2 emissions are lower using bio-additive B, and smoke emission increase with bio- additive B.
Keyword: Biosolar B30, Biodiesel, Bioadditive, Diesel Engine Performance, Characterization test

Judul: Pengaruh Minyak Atsiri sebagai Bioaditif pada Biosolar B30 dalam Menurunkan Kadar Air dan Partikulat
Abstrak: Biodiesel is an alternative fuel that can replace the use of fossil fuels, but it has several drawbacks such as high on water, and particulate content. One way to reduce the impact of this deficiency is by adding bioadditives to improve its quality. This research aims to determine the best essential oils amongs turpentine, clove terpene oil, citronella oil, and rhodinol, to develop bioadditive formulations from the combination of the said essential oils and to get the effective concentration to reduce water, and particulates content. The research was conducted by mixing citronella oil, turpentine, clove terpene, and rhodinol, as well as a bioadditive formulas of a mixture of said essential oils, namely bioadditive A (Turpentine: Clove Terpen: Citronella Oil) with variations of A1, A2, & A3, and bioadditive B (Trepentine: Clove Terpenes: Rhodinol) with variations of B1, B2, & B3 into biosolar B30. The tests carried out were the water content test, as well as the particle count test. The results showed that the largest decrease in water content was produced by turpentine at a concentration of 1% with a percentage decrease of 19.11%, and bioadditive A1 at a concentration of 0.1% with a percentage decrease of 4.8%. The best particulate reduction was found in bioadditive B1 with the percentage reduction values for sizes 4 microns, 6 microns, and 14 microns were 93%, 95%, and 78%, respectively., Biodiesel merupakan bahan bakar alternatif yang dapat menggantikan penggunaan bahan bakar fosil, namun memiliki kekurangan seperti tingginya kadar air, dan kadar partikulat. Salah satu cara untuk mengurangi dampak dari kekurangan ini adalah dengan cara melakukan penambahan bioaditif untuk meningkatkan kualitasnya. Penelitian bertujuan untuk mengetahui minyak atsiri terbaik diantaranya minyak terpentin, clove terpen, minyak sereh wangi, dan rhodinol, lalu mengembangkan formulasi bioaditif dari kombinasi minyak atsiri yang digunakan, serta mendapatkan konsentrasi yang efektif untuk menurunkan kadar air, dan partikulat. Penelitian dilakukan dengan cara mencampurkan minyak sereh, terpentin, clove terpen, dan rhodinol, serta formula bioaditif campuran minyak atsiri yaitu bioaditif A (Terpentin: Clove Terpen: Citronella Oil) dengan variasi A1, A2, & A3, dan bioaditif B (Terpentin: Clove Terpen: Rhodinol) dengan variasi B1, B2, & B3 ke dalam biosolar B30. Pengujian yang dilakukan adalah uji kadar air, serta uji kadar partikulat (particle count). Hasil penelitian menunjukan bahwa penurunan kadar air terbesar dihasilkan oleh terpentin pada konsentrasi 1% dengan persentase penurunan sebesar 19.11%, dan bioaditif A1 pada konsentrasi 0.1% dengan persentase nilai penurunan sebesar 4.8%. Penurunan kadar partikulat terbaik didapatkan pada bioaditif B1 dengan persentase nilai penurunan untuk ukuran 4 mikron, 6 mikron, dan 14 mikron masing-masing adalah 93%, 95%, dan 78%.
Keyword: bioaditive, biosolar B30, essential oil, particulate content, water content

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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