Judul: Optimalisasi pemurnian silikon berbahan dasar arang sekam padi menggunakan reaktor tertutup
Abstrak: High silica (SiO2) concentration in charcoal rice husk could be used as silicon with 40-60% level of purity. Low purity is caused by the effect of oxygen involved in the reduction process. The aim of this research was to optimize reduction process of silica from charcoal rice husk to obtain silicon with high purity level. The optimization process of silica reduction was conducted in closed reactor using alumina and stainless steel tube with magnesium as reducing agent in mass ratio of SiO2 and Mg 1:1 and 1:2. The reduction products were leached by HCl 10% at the first step, and a mixture of 2M HCl and CH3COOH 25% at the second step. Silicon products were characterized by X-ray diffraction (XRD) and MATCH 2 program. In mass ratio of SiO2 and Mg 1:1, quantitative value of XRD (QXRD) silicon in alumina tube reactor (22%) was higher than that in the stainless steel tube reactor (16%). In alumina tube reactor, QXRD silicon in mass ratio of SiO2 and Mg 1:1 that value was lower than that of 1:2 (50%). The acid leaching process removed major impurities, such as MgO, Mg2SiO4, and SiO2. The highest purity of silicon was produced from alumina tube reactor with mass ratio of SiO2 and Mg 1:2.
Keyword: Bogor Agricultural University, silicon, silica, closed reactor, charcoal rice husk

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: Prevalence of Bird Lice on Rock Pigeon (Columba livia) in 99Wonderland Park, Selangor, Malaysia
Abstrak: Rock Pigeon (Columba livia) have coexisted with humans for thousands of years and are used for various purposes such as food and in sports. Rock pigeons may have the potential to be infested with a wide range of ectoparasites, which can have a significant impact on their life cycle. This study aims to measure the prevalence of Columba livia with bird lice in 99Wonderland Park, Selangor, Malaysia in the year 2020 and to ascertain the impact of bird lice on the health of these infested birds. Data were collected from clinical records for the month of January to December in the year 2020 from 99Wonderland Park, Selangor, Malaysia. Lice were identified in 42 of the 80 Rock pigeons examined so, the overall prevalence of lice infestations was 52.5%. The prevalence of ectoparasites was found to be higher in young Rock pigeons (60.4%) as compared to adult Rock pigeons (37.4%). Columbicola columbae (wing lice) and Colpocephalum turbinatum (body lice) are two species of lice that have been detected. Body lice were more prevalent in young Columba livia birds at 47.6% whereas wing lice were more prevalent in adult Columba livia birds at 16.7%. Most of the lice were found in the thorax and abdomen area followed by the head and neck area., Merpati Batu (Columba livia) telah hidup berdampingan dengan manusia selama ribuan tahun dan digunakan untuk berbagai keperluan seperti makanan dan olahraga. Merpati batu dapat terinfestasi dengan berbagai ektoparasit, yang dapat berdampak signifikan pada siklus hidup mereka. Penelitian ini bertujuan untuk mengetahui prevalensi Columba livia dengan kutu burung di 99 Wonderland Park, Selangor, Malaysia pada tahun 2020 dan untuk memastikan dampaknya terhadap kesehatan burung yang terinfestasi. Data dikumpulkan dari catatan klinis dari bulan Januari hingga Desember tahun 2020 dari 99Wonderland Park, Selangor, Malaysia. Kutu diidentifikasi pada 42 dari 80 merpati batu yang diperiksa sehingga, prevalensi keseluruhan infestasi kutu adalah 52,5%. Prevalensi ektoparasit ditemukan lebih tinggi pada merpati batu muda (60,4%) dibandingkan dengan merpati batu dewasa (37,4%). Columbicola columbae (kutu sayap) dan Colpocephalum turbinatum (kutu badan) adalah dua spesies kutu yang telah ditemukan. Kutu badan lebih banyak ditemukan pada burung Columba livia muda sebesar 47,6% sedangkan kutu sayap lebih banyak ditemukan pada burung Columba livia dewasa sebesar 16,7%. Sebagian besar kutu ditemukan di daerah dada dan abdomen diikuti daerah kepala dan leher.
Keyword: Columba livia, prevalence, ectoparasite, wing lice, body lice, Columba livia, prevalensi, ektoparasit, kutu sayap, kutu badan