Judul: Pemanfaatan Jerami Padi Dalam Pembuatan Papan
Abstrak: Process of paddy straw can board production for material interior wall construction. This research propose on the processing of paddy straw as board interior wall. Paddy straw dried in an oven at 60 oC for 3 hours, then milled into a powder form with size a 10 mesh. Than characteristic physical experiment, paddy straw board can density 0.341 g/cm3, water absorbtion 68.74%, firmnes press 12.72 kg/cm2 and internal bond 0.035 kg/cm2. Experiment of characteristic acoustic can a good sound absorpsi. Board with thickness 3 cm can a good efficiency than board another
Keyword: Bogor Agricultural University, paddystraw and physical properties., efficiency, Board

Judul: Kualitas Papan Semen dari Sekam Padi (Oryza sativa Linn)
Abstrak: INTRODUCTION: Recently, plenty of waste of paddy as a lignosellulosic organic material was obtained due to increasing. However, utilization of rice hull still not optimally done and it has low economic value. In some countries, the lignosellulosic waste becomes a problem because it pollutes the environment. Many researches showed that rice hull can be used in several necessity product, such as, alternative energy source, particle board, and cement bonded board and this research was to find out the substitution of solid wood and it may solve environmental problem. The objective of the study was to evaluate the effect of cement portion variation on the physical and mechanical properties of cement bonded boards from rice hull. MATERIAL AND METHOD: The cement bonded board were manufacture using rice hull particles (Oryza sativa,L.), portland cement, calcium chloride, and water. The rice hull particles were immersed in cold water for 24 hours prior to board manufacture. The rice hull-cement-water ratios applied were 1,00 : 2,75 : 1,38 ; 1,00 : 3,00 : 1,50, and 1,00 : 3,25 : 1,63 with used calcium chloride at 2 % of total weight. Manufacturing process the cement bonded board from rice hull can be divided into several operations including: the preparation of a raw material, mixing, mat forming (30 cm x 30 cm x 1 cm) at target density was 1,2 g/cm³, pressing (35 kgf/cm²), setting (60ºC for 24 hours), hardening (room temperature for 2 weeks), drying (80ºC for 10 hours), conditioning (2 weeks) and the test of physical and mechanical properties of cement bonded board. This experiment was designed using a Completely Randomized Design (CRD) with one treatment and three replicates. RESULT: Result showed that moisture content of cement bonded board is 8,01- 9,33%, density 1,15-1,26 g/cm³, for immersion period of 2 hours showed thickness swelling 0,12-0,35%, linear expansion 0,21-0,32%, and water absorption 20,98-24,78% while the immersion period of 24 hours thickness swelling 0,32-0,51%, linear expansion 0,29-0,33%, and water absorption 24,89-28,14%, modulus of elasticity 14.324,16-22.488,66 kgf/cm², modulus of rupture 22,99-29,63 kgf/cm², internal bond 0,45078-0,58797 kgf/cm², and screw holding strength 19,75-23,39 kgf. Physical properties of the boards requirement fulfilled the JIS A 5417 (1992) standard and Bison (1975) while mechanical properties of the boards were MOE, MOR, IB, screw holding strength did not fulfill the JIS A 5417 (1992) standard and Bison (1975). Result of research showed that increase in cement portion did not significantly effect the properties of cement bonded board from rice hull.
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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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