Judul: Pemurnian Silikon Asal Arang Sekam Padi Menggunakan Magnesium dan Gas Nitrogen
Abstrak: Rice husk charcoal is an agricultural waste containing 72% silica that is a potential alternative source of silicon. Silicon from silica derived from the husk was purified by reduction using magnesium and subsequently washing with HCl 3%. Oxygen in air is suspected to react with the magnesium during the reduction process, such that the silica form was still present in the reduction product. The objective of this research is to compare the purity of silicon obtained from silica reduction using magnesium under nitrogen gas flow and under ambient air flow. The nitrogen gas was used to avoid oxygen from reacting so the magnesium only reacted with the silica. The silicon was characterized using X-Ray Diffraction and data were analyzed using Match 2 software. The yield of silicon from the reduction process without nitrogen gas flow was 59%. This is smaller than the 64% silicon yield obtained from the reduction process using nitrogen gas flow. Application of nitrogen gas flow to the silica reduction process with magnesium increases the silicon yield and affecyed the silicon purity.
Keyword: Bogor Agricultural University (IPB), silicon, silica reduction, rice husk, nitrogen gas

Judul: Penambahan magnesium berlebih dalam menghasilkan silikon murni dari sekam padi sebagai bahan semikonduktor
Abstrak: Rice is one of the most important cultivated plants in human civilization. Rice is also one of the main carbohydrate source the majority of the population in Indonesia. Central Statistics Agency (BPS 2012), estimates that in 2012 rice production reached 68.59 million tons, up by 2.84 million tonnes (4:13%) than in 2011. Seeing this, then it will appear in the form of agricultural waste rice husk. Most of the waste generated from the processing of rice had only burned or thrown away (Azadi et al 2010). Utilization of rice husk furnace developed by IPB since 2007, generating more waste in the form of waste rice husk (Irzaman et al 2007). Rice husk charcoal is known to contain at 95.14% silicon dioxide (Supaman et al 2010) and has the potential to produce pure silicon with a rate 40.78% (Hikmawati 2010) and 42.29% (Ahmad L 2012). This study aimed to examine the characteristics of silicon powder obtained from rice husk by chemical reduction method, which reduces the silicon dioxide using magnesium (Mg) powder to vary the ratio of the amount of silicon dioxide with magnesium and washing with a solution of HCl in the purification. Silicon dioxide and silicon obtained will be analyzed using X-Ray Difraction (XRD), Scanning Electron Microscope-Energy Distersive X-Ray (SEM-EDX), LCR meter and I-V meter. Manufacture of silicon through three (3) phases, husk charcoal, silicon dioxide and silicon. Husk charcoal through several stages. At first the rice husk is dried with the aid of sunlight with the purpose of accelerating the combustion process. Then the rice husks were weighed at 5000 grams (5 kg), entered into a husk furnace and continued with the process of burning, then the rice husk charcoal weighed. In this process produced rice husk for 1440 grams (1.44 kg). Rice husk as much as 40 grams put in porcelain dish and baked in a kiln at a temperature initially 400 °C for 2 hours, subsequent heating to temperatures of 1000 °C for 1 hour with the temperature rising rate setting by 1 °C/minutes and 5 ° C/minutes. After the ash obtained by burning weighed, then washed rice husk ash using hydrochloric acid (HCl) 3% technical which 12 mL of HCl 3% for 1 gram of technical rice husk ash, then heated over a hotplate with temperature settings 200 °C and stirred with magnetic stirrer at a speed of 240 rpm for 2 hours. Subsequently washed with hot distilled water (temperature of about 90-100 °C) repeatedly until acid-free (tested with litmus paper), and then filtered through ash-free paper. Screening results (residue separated from the filter paper) is inserted in the porcelain dish is then heated in a furnace at temperatures of 1000 °C for 1 hour with a temperature rise of 1 °C/minutes and 5 °C/minutes until the silicon dioxide remaining white. The samples were cooled in the furnace and weighed, then the result is tested SEM-EDX, LCR meter and I-V meter (Ahmad L 2012). The next process is to get silicon, silicon dioxide mixed with magnesium powder with a reductant that vary the ratio ranging from ratio
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Judul: Pengaruh Infeksi Haemoproteus columbae (Kruse, 1890) Pada Burung Merpati Dan Cara Penanggulangannya
Abstrak: Haemoproteus columbae merupakan paras it yang menyerang sel-sel darah merah burung rnerpati. Siklus hidupnya kompleks dan dapat dibagi menjadi dua yaitu siklus hidup asexual terjadi delam tubuh burung merpati dan siklus hidup sexual terjadi dalam tubuh lalat dari famili Hippoboscidae sebagai vektor. Stadium yang nampak dalam peredaran darah perifer hanyalah garoetosit yang dapat dibedakan menjadi dua yaitu gametosit jantan (mikrogametosit) dan gametosit betina (makrogametosit).
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