Judul: Pengaruh Penambahan Sludge pada Konversi Jerami Padi Menjadi Biogas
Abstrak: The principal problems which have become the main focus of society are environmental problem and energy scarce. The main cause of the problems is the high consumption of fossil fuels. The purpose of this research is to find out effect of sludge composition on rice straw convertion to biogas. The fermentation were conducted with 1.5 L reactors and fermentation during 30 days. This aims to determine the effect of the use of sludge on the conversion of rice straw into biogas. Activated sludge were use as additional substrate with two composition, 225 g on the composition rice straw:sludge 5:3 and 375 g in composition rice straw:sludge 3:5. The maximum gas production was reached 18.382 L/kg TS in 1st running and 11.602 L/kg TS in 2nd running or 27.67816 L/g VS (1st running) and 18.93871 L/g VS (2nd running) by composition rice straw:sludge 3:5. The highest phosphate levels produced by rice straw:sludge 5:3 was 0.60 %, the carbon highest in rice straw:sludge 3:5 was 38.40 %, and nitrogen in rice straw:sludge 5:3 was 1.80 %.
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Judul: Pengaruh Penambahan Sludge dan Pengecilan Ukuran Bahan pada Konversi Sampah Organik Pasar Menjadi Biogas
Abstrak: The principal problems which have become the main focus of society are environmental problem and energy scarce. The main cause of the problems is the high consumption of fossil fuels. The purpose of this research is to find out effect of sludge composition and particle size reduction on organic waste convertion to biogas. The fermentation were conducted with 1.5 L reactors and fermentation during 21 days. Composition of organic waste from traditional market were banana leaf 7.5%, corn husk 24.2%, bitter melon 14.8%, cabbage 19.9%, chicory 6.2%, water spinach 8.0%, mustard greens 8.0%, carrots 11.5% (w/w). The maximum gas production was reached 14.414 L/kg TS in 1st running and 22.028 L/kg TS in 2nd running or 0.005215 L/g VS (1st running) and 0.005172 L/g VS (2nd running) with COD value was 0.459 g/kg by composition 3:5 and size 0.1 to 0.5 cm. All treatments had a pH interval 4.80 to 6.67. The highest phosphate levels produced by sludge 5:3 (0.1 to 0.5 cm) was1.97 %, the carbon highest in sludge 3:5 (1.5 to 2 cm) was 10.25 %, and nitrogen in sludge 5:3 (1.5 to 2 cm) was 2.20 %.
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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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