Judul: Analisis Variasi Diameter Tandon Tungku dan Biopelet terhadap Efisiensi Energi Bahan Bakar (Studi Kasus Sekam Padi dan Kulit Kopi)
Abstrak: Biopellet is the solid fuel biomass with the better density and uniformity of size than its biomass. The variables affecting burning completion of fuel are size of particles and material characteristics. The purpose of the research was to compare efficiency of fuel biopellet with its biomass, and analyze the influence of biopellet diameter and reservoir furnace to energy efficiency. Materials researched were rice husk and coffee comb. Analysis of data used design group complete. The coffee comb was not good enough as alternative fuel for furnace. Rice husk and its biopellet in processing of boiling 0.5 L water produced energy efficiency approximately same about 16%. Temperature of ember biopellet rice husk higher and durable than its rice husk about 6700C, therefore boiling time was faster than its biomass about 3 minutes. The bigger efficiency of each diameter biopellet to diameter reservoir furnace, were 16.9% with biopellet diameter was 4 mm used reservoir 12 cm, 16.6% with diameter biopellet was 5 mm used reservoir 9 cm, and 15.5% with biopellet diameter was 16 mm used reservoir 6 cm. The result indicated that the sectional area material to oxygen directly proportional affected energy efficiency
Keyword: 

Judul: Uji keragaan biopelet dari biomassa limbah sekam padi (Oryza sativa sp.) sebagai bahan bakar alternatif terbarukan
Abstrak: The abundance of rice husks in Indonesia is a potential source of biomass that can be converted into biomass pellet (biopellets). Pelletization can improve the quality and burning characteristic of the biomass. The purpose of this study is to improve the quality of rice husks biopellets by combining the rice husks powders and the rice husks charcoal. Carbonization process was done by using kiln drum whose height is 30 cm and diameter is 19 cm for ±5 hours at a temperature of 400 0C. The percentage of rice husks charcoal used was 0%, 10%, and 20%. Densification process was done by pellet mill whose capacity is 300 kg/h with a dies diameter of 8 mm. Used cooking oil was added to the raw material for 4.77% w/w. Biopellets was sun-dried for 4 hours. Then, the physico-chemical properties and the combustion characteristics were tested. Mass and energy flows were measured by using method of input-output analysis for the biopellets production process. The results of this research showed that the addition of rice husk charcoal into the rice husk biopellet generated a different effect significantly to the moisture content, ash content, volatile matter, bulk density, and the heating value of rice husks biopellet, but there was no significant effect to the level of fixed carbon, firmness, consumption rate, and the efficiency of combustion. Based on the physico-chemical properties and the combustion characteristics, rice husk biopellets that contained 10% of husk charcoal has the best quality. It has 3.60 % of moisture content, 17.47% of ash content, 72.86% of volatile matter, 9.68% of fixed carbon, and 728.43 kg/m3 of bulk density. The heating value of the biopellets was 4329.63 kcal/kg, while the firmness was 10.54 kg/cm2. In addition, the consumption rate of the biopellets was 1.84 kg/h while the efficiency of combustion was 8.34%. The production of rice husk biopellets on a laboratory scale produced yield of 18.67%. Biopellets increased the heating value of ricu husk for 25.49%.
Keyword: 

Judul: Infeksi leucocytozoon Smithi (Laveran dan Lucet, 1905) pada kalkun
Abstrak: Leucocytozoon smithi adalah parasit darah yang menyebabkan leucocytozoonosis pada kalkun, dan termasuk dalam genus Leucocytozoon yang perkembangan skizogoninya terja- di dalam sel-sel endotel dan sel-sel parenkhim hati, jan- tung, ginjal dan organ-organ lain dari unggas. Genus ini menghasilkan skizon yang besar. Gametogoninya terjadi di dalam sel-sel darah dan sel yang terinfeksi dapat berubah bentuk dan mengambil bentuk kumparan. Parasit ini tidak menghasilkan pigmen dan ditularkan oleh lalat penghisap darah dari genus Simulium. Infeksi kalkun terjadi pada saat sporozoit masuk ke dalam peredaran darah dan selanjutnya masuk ke dalam sel- sel parenkhim hati. Siklus hidupnya mirip dengan siklus hidup L. simondi seperti yang diuraikan di bawah ini. Skizogoni yang terjadi di dalam hati menghasilkan skizon hepatik. Skizon hepatik dewasa menghasilkan merozoit dan sinsitia. Merozoit dari skizon hepatik memasuki eritroblas dan eritrosit dan membentuk gametosit bulat, sedangkan sinsitianya dapat masuk ke dalam sel-sel RES dan kemudian membentuk megaloskizon. Megaloskizon dewasa menghasilkan merozoit yang kemudian masuk ke dalam limfosit dan leukosit lain membentuk gametosit memanjang. Gametositgametosit ini akan menjadi makrogametosit dan mikrogametosit. Perkembangan parasit dalam tubuh vektor (Simulium), segera dimulai setelah vektor menghisap darah kalkun yang mengandung gametosit ini. Dalam tubuh vektor ini akan ter- jadi pembuahan makrogamet oleh mikrogamet (tahap gametogoni). Dari pembuahan ini dihasilkan zigot yang bergerak (ookinet). Ookinet akan masuk dinding usus vektor untuk memulai tahap sporogoni yang menghasilkan sporozoit. Sporozoit ini akan menuju ke kelenjar ludah dan dari sini dapat dipindahkan lagi ke tubuh kalkun pada saat vektor menghisap darah. Vektor untuk L. smithi adalah S. occidentale, S. nigroparvum, S. slossonae, S. nigritarse. L. smithi berbahaya, terutama bagi kalkun-kalkun muda. Mortalitasnya dapat mencapai 90 persen. Gejala klinis yang ditimbulkannya antara lain anorexia, lemas dan cenderung untuk duduk, kekurusan dan kelemahan, sesak nafas dan in- koordinasi dan terjungkal terlihat pada stadium akhir dan selanjutnya kalkun mengalami coma kemudian mati…dst
Keyword: