Judul: Puzzle Making and Characterization of Activated Carbon from Coconut Shell as Exhaust Gas Filters
Abstrak: Emisi gas buang adalah sisa hasil pembakaran bahan bakar di dalam mesin pembakaran dalam maupun mesin pembakaran luar yang dikeluarkan melalui sistem pembuangan mesin. Tujuan penelitian ini menguji kualitas karbon aktif tempurung kelapa berdasarkan Standar Nasional Indonesia (SNI), mengetahui sifat fisika dan kimia karbon aktif tempurung kelapa dan kemampuanya sebagai adsorben. Tempurung kelapa terlebih dahulu dikarbonisasi dan aktivasi secara kimia dan fisika. Saat aktivasi dengan variasi waktu (60 menit, 80 menit, 110 menit, 140 menit) yang dilakukan untuk memperlihatkan perubahan dari karakteristik karbon aktif. Karbon aktif yang telah dibuat kemudian dikarakterisasi menggunakan SEM untuk melihat morfologi permukaan dengan variasi ukuran partikel. Hasil analisis SEM memperlihatkan peningkatan jumlah pori pada karbon aktif tempurung kelapa yang ditunjukkan dengan seragamnya bentuk pori dan semakin besarnya luas permukaan pori.
Keyword: Bogor Agricultural University, Institut Pertanian Bogor, IPB, Activated carbon, Coconut shell, Exhaust emission, kualitas karbon aktif, emisi gas buang, arang aktif

Judul: Activated Charcoal Made from Kluwak, Palm Kernel, Coconut, and Candlenut Shells as an Adsorbent for Motor Vehicle Gas Emissions
Abstrak: Arang aktif biasa dipakai dalam proses pemurnian udara, gas, larutan atau cairan, dan proses perolehan kembali suatu logam. Arang aktif memiliki pori-pori yang lebih terbuka sehingga daya jerapnya lebih tinggi dibandingkan arang biasa. Bahan yang dapat digunakan sebagai bahan baku arang aktif adalah limbah perkebunan seperti tempurung kluwak, kelapa sawit, kelapa, dan kemiri. Penelitian ini bertujuan membandingkan arang aktif dengan mutu terbaik dari bahan dasar tempurung untuk menurunkan kadar gas pencemar udara seperti gas CO, NO2, dan SO2 yang berasal dari emisi kendaraan bermotor yang dapat merusak lingkungan dengan metode kajian literatur. Hasil penelitian menunjukkan keempat tempurung menghasilkan arang aktif dengan mutu yang baik. Tempurung kluwak menghasilkan arang aktif dengan kandungan karbon terikat tertinggi, yaitu sebesar 96,90% serta daya jerap iod sebesar 996,96 mg/g yang memenuhi SNI 06-3730-1995. Arang aktif tempurung kluwak memiliki efektivitas terhadap penurunan konsentrasi gas CO yang paling baik, yaitu sebesar 98,02%, sedangkan efektivitas terhadap penurunan konsentrasi gas NO2 dan SO2 yang paling baik dimiliki oleh arang aktif tempurung kelapa, yaitu 93,50% terhadap gas NO2 dan 76,79% terhadap gas SO2. Kata kunci: adsorpsi, arang aktif, emisi, karbon terikat, tempurung, Activated charcoal is commonly used to purify air, gas, solution, or liquid, and recover a metal. Activated charcoal has pores that are more open so that it has a higher adsorption capacity than ordinary charcoal. Raw materials used as activated charcoal include leftover shell from kluwak, palm kernel, coconut, and candlenut shell. This study compares and determines which shell-based activated charcoal has the best quality to reduce air pollutant gases such as CO, NO2, and SO2 gases from motor vehicle emissions that can damage the environment using a literature review method. The results showed that the four shells produced good quality activated charcoal. Kluwak shell produces activated charcoal with the highest fixed carbon content, 96.90% and iodine adsorption capacity of 996.96 mg/g, complying with SNI 06-3730-1995. Kluwak shell activated charcoal has the most excellent effectiveness in reducing the concentration of CO gas from motor vehicle emissions compared to activated charcoal from the other three shell types, which is 98.02%. Meanwhile, coconut shell-activated charcoal performs the best effectiveness in reducing NO2 and SO2 gas concentrations, which has 93.50% for NO2 and 76.79% for SO2. Keywords: activated charcoal, adsorption, emission, fixed carbon, shell
Keyword: Activated charcoal, Adsorption, Emission, Fixed carbon, Shell

Judul: The Effects of Hypothyroidism in the Fertility of Male Rats
Abstrak: Thyroid hormones are involved in the development and maintenance of virtually all tissues. The purpose of the study is to understand effects of the neonatal hypothyroidism in the fertility of male rats. Recent studies with juvenile rats indicate that changes in thyroid function early in life have a major impact on the endocrine and/or paracrine factors regulating testicular growth and function. However, one should keep in mind that hypothyroidism is a complex hormonal dysfunction rather than a single hormonal defect. Hypothyroidism has been also shown to reduce the secretion of GnRH (gonadotropins releasing hormone), LH (Luteinizing Hormone), FSH (Follicle Stimulating Hormone), GH (Growth Hormone) and testicular testosterone in rats. Therefore, many of the testicular changes observed in prolonged hypothyroidism could result in some degree of diminished levels of the aforementioned hormones. The transient neonatal hypothyroidism model results in the unnatural testicular development and in sperm production in neonates hence resulting in decreased fertility upon puberty.
Keyword: Hypothyroidism, Neonates, Testicular Growth, Fertility