Judul: The Effect of Variation in Temperature and Duration on Deoxygenation and Cracking Reaction of RPO in Bioavtur
Abstrak: Vegetable oils can be converted into bioavtur because they have triglycerides that can be converted through deoxygenation and cracking into bioavtur hydrocarbon. Refined Palm Oil (RPO) is also vegetable triglyceride that may be converted into bioavtur by similar mechanism. This study aims to convert RPO into hydrocarbons equal to avtur through deoxygenation and cracking with various temperature and reaction duration. In the preliminary research, RPO was made from degumming process of CPO, heated with solid catalyst NiMo in a reactor at temperature of 300, 400 and 450 oC, with addition of hydrogen at pressure of 50 bar and stirring for 5 h with sampling every hour to obtain the suitable temperature conditions. At principal research, the same reaction was conducted at selected temperature conditions with sampling every 30 minutes after initial heating for 1 h. Observation was conducted for parameters density, phase change at low temperatures (-15 and -55 oC), GC-MS and FTIR analysis. Preliminary research showed that only at temperature of 450 oC, the product had liquid phase up to -55 oC and the density equal to jet fuel. At this temperature condition (450 oC ), the results showed that the best deoxygenation and cracking reaction was at pressure of 50 bar, in 3 h duration. The physical properties of the products were having the best deoxygenation reaction, having similar properties with aviation fuel, and density of 0.8105 g/cm3, still on liquid phase at low temperature up to -55 oC with the composition of mostly C7 - C12 hydrocarbons.
Keyword: bioavtur, refined palm oil, deoxygenation, cracking

Judul: Characterization of Biodiesel Quality from Palm Oil Based on Different Set of Temperature Level by Using Circulation Reactor
Abstrak: The characterization of biodiesel quality from palm oil based on different set of temperature level by using circulation reactor has been investigated. The research was done in 2 phases. The first experiment was done to characterize raw material to decide the following reaction step. The main research was done in 3 temperature conditions (50, 60, and 70 oC) with interval of 1, 5, 10, 15, 20, 30, 60, and 90 minutes. Molar ratio of methanol to oil at 6:1 and KOH catalyst was 1% of oil weights. Data processing used split plot randomized complete design and continued by Duncan test as necessary. Biodiesel preparation was done with one transesterification step, since free fatty acid contents of palm oil was low (0,32%). The result indicated that the higher the temperature and reaction time the higher the biodiesel quality, based on the lower the acid value, viscosity, total and combined glycerol, and high on methyl esters content. The acid value on temperature 50, 60, and 70 oC was 0,44; 0,41; and 0,40 mg KOH/g, the value of total glycerol was 0,33; 0,29; and 0,26%, and combined glycerol was 0,32; 0,27; and 0,25%, the viscosity was 13,59; 12,34; and 11,94 cSt, the density was 864,5; 864,8; and 862,7 kg/m3, and methyl esters content was 99,05; 99,13; and 99,23%, respectively. Based on data analysis, the optimum condition of circulation reactor was 15 minutes for 70 oC, 20 minutes for 60 oC, and 30 minutes for 50 oC.
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Judul: Karakteristik Anatomi Skelet Kepala Buaya senyulong (Tomistoma schlegelii).
Abstrak: Buaya sepit atau senyulong (Tomistoma schlegelii) merupakan jenis buaya asli Indonesia yang berhabitat di sungai-sungai Sumatera, Kalimantan, dan juga pedalaman Sulawesi. Salah satu ciri khas buaya senyulong adalah bentuk moncong yang runcing dan sempit, namun hingga saat ini informasi mengenai struktur skelet kepala buaya senyulong sangat terbatas. Penelitian ini bertujuan untuk mempelajari karakteristik anatomi skelet kepala buaya senyulong yang dikatikan dengan fungsi dan perilakunya. Penelitian dilakukan secara eksploratif dengan melakukan pengamatan, pencatatan, dan pengambilan gambar dari skelet kepala buaya senyulong. Skelet kepala berukuran panjang 70 cm, lebar 29 cm, dan tingggi 17 cm dengan permukaan kasar pada os nasale, os frontale, os maxilla, os mandibula, os lacrimale, os jugale. Jumlah gigi pada buaya ini sebanyak 78 buah, terdiri dari 4 buah gigi premaxila, 16 buah gigi maxila, dan 19 buah gigi mandibula. Pada regio orbitalis ditemukan dua pasang fenestrae temporales yang berkembang baik. Fenestra supratemporale merupakan lubang oval yang membentang di sepanjang os parietale. Fenestra infratemporale berbentuk segitiga dan dibatasi oleh os squamosum, os postorbitale, os jugulare, dan os quadratum. Os mandibula hewan ini mempunyai symphysis mandibularis yang panjang yaitu garis yang melintang di corpus mandibulae. Secara fungsional ukuran symphysis mandibularis berkaitan dengan adaptasi hewan terhadap diet makan.
Keyword: kepala, moncong, Tomistoma schlegelii