Judul: Improving Microbial Fuel Cell Performance from Fisheries Liquid Waste Using Boost Converter Device
Abstrak: Listrik merupakan kebutuhan pokok dalam kehidupan sehari-hari. Energi fosil biasanya digunakan untuk menghasilkan listrik dan energi yang tidak terbarukan, sehingga akan habis apabila tidak ada inovasi yaitu berupa energi terbarukan. Limbah cair perikanan dapat menghasilkan listrik dengan sistem Microbial Fuel Cell (MFC). Akan tetapi, listrik yang dihasilkan relatif kecil. Tujuan penelitian yaitu meningkaatkan tegangan listrik dari limbah pemindangan ikan pada sistem Microbial Fuel Cell menggunakan rangkaian tambahan alat boost converter. Penelitian dilakukan dengan menggunakan 5 sistem MFC yang dirangkai secara seri dan disambungkan ke alat boost converter. Nilai elektrisitas sistem MFC dengan rangkaian alat boost converter yaitu tegangan sebesar 12,13±0,87 V, nilai arus 0,86±0,20 mA, dan nilai daya 10,50±3,11 mW, sedangkan tanpa rangkaian alat boost converter yaitu nilai tegangan sebesar 2,24±0,26 volt, nilai arus 0,17±0,03 mA, dan nilai daya 0,38±0,11 mW. Peningkatan elektrisitas pada sistem MFC menunjukkan bahwa rangkaian alat boost converter berfungsi. Sistem MFC dapat menurunkan nilai BOD, COD, dan TAN., Electricity is a basic necessity in everyday life. Fossil energy is typically used to generate electricity, and non-renewable energy sources will eventually be depleted without innovation in the form of renewable energy. Liquid waste from fisheries is a commodity that can generate electricity through Microbial Fuel Cell (MFC) systems. However, the electricity generated is relatively small. The research aimed to increase the electrical voltage from fish curing waste in a Microbial Fuel Cell system by using an additional boost converter circuit. The research was conducted using 5 MFC systems connected in series and connected to a boost converter device. The electrical values of the MFC system with the boost converter circuit were a voltage of 12.13±0.87 V, a current of 0.86±0.20 mA, and a power of 10.50±3.11 mW. Meanwhile, without the boost converter circuit, the voltage value was 2.24±0.26 volts, the current was 0.17±0.03 mA, and the power was 0.38±0.11 mW. The increase in electricity in the MFC system indicated that the boost converter circuit functioned properly. The MFC system was able to reduce BOD, COD, and TAN values.
Keyword: boost converter, limbah cair, listrik, MFC

Judul: Kinerja Microbial Fuel Cell Pembangkit Biolistrik dengan Variasi Rasio Luas Elektroda dan Volume Limbah Cair Perikanan.
Abstrak: Limbah cair perikanan dapat menyebabkan pencemaran lingkungan jika tidak dikelola dengan baik. Pengolahan limbah cair perikanan secara konvensional memerlukan biaya dan energi yang cukup tinggi. Microbial fuel cell (MFC) dapat membangkitkan energi listrik dari penguraian bahan organik pada limbah dengan memanfaatkan mikroorganisme. Penelitian dilakukan menggunakan MFC satu bejana dengan rasio luas elektroda dan volume limbah cair perikanan yang berbeda yaitu 1:80 cm2/cm3, 1:40 cm2/cm3 dan 1:8 cm2/cm3. Tegangan listrik tertinggi terdapat pada perlakuan rasio 1:80 cm2/cm3 sebesar 428.98 mV. Arus listrik tertinggi terdapat pada perlakuan 1:40 cm2/cm3 sebesar 3.26 mA. Rapat daya listrik tertinggi terdapat pada perlakuan 1:40 cm2/cm3 sebesar 1 185.87 mW/m2. Nilai chemical oxygen demand (COD) mengalami penurunan sebesar 62% pada perlakuan rasio 1:8 cm2/cm3 dan biochemical oxygen demand (BOD) mengalami penurunan sebesar 42% pada perlakuan rasio 1:80 cm2/cm3. Nilai mixed liquor suspended solids (MLSS) dan mixed liquor volatile suspended solids (MLVSS) mengalami peningkatan sebesar 1 471% dan 1 725% pada perlakuan rasio 1:40 cm2/cm3. Nilai pH mengalami meningkat menjadi 7.5-8.4. Nilai total amonia nitrogen (TAN) mengalami penurunan sebesar 89-93%.
Keyword: limbah cair perikanan, listrik, luas elektroda, microbial fuel cell

Judul: Lejeuneaceae Subfamily Ptychanthoideae (Hepaticae) in  West Java
Abstrak: Subfamily Ptychanthoideae of the family Lejeuneaceae (Hepaticae) in West Java is still poorly known. Publications on this subfamily are out of dated and written in the 19th or early of 20th century. The last taxonomic treatment of Ptychanthoideae of West Java was in 1933, many species names have changed since then. Studies on Ptychanthoideae of West Java are urgently needed. Studies on the Ptychanthoideae were based on the specimens collected from West Java. A total number of 361 of specimens deposited in the Herbarium Bogoriense (BO), Herbarium Biotrop (BIOT), Gottingen Herbarium (GOET) and Bangi Herbarium (UKMB) were examined, those are old and several recent specimens collected in West Java. Recent collections were made from Telaga Warna, Ciater, Gunung Halimun Salak National Park, Cibodas Botanical Garden, Bodogol Education Center and Conservation (Gunung Gede Pangrango National Park), University of Indonesia Campus Depok, including several collections from Banten Province. Twenty four species of Lejeuneaceae subfamily Ptychanthoideae are known from West Java, belonging to 8 genera namely Acrolejeunea (Spruce) Schiffn. (2 species), Archilejeunea (Spruce) Schiffn. (1 species), Lopholejeunea (Spruce) Schiffn. (10 species), Mastigolejeunea (Spruce) Schiffn. (3 species), Ptychanthus Nees (1 species), Schiffneriolejeunea Verd. (1 species), Spruceanthus Verd. (2 species) and Thysananthus Lindenb. (4 species). Two new records of Ptychanthoideae: Mastigolejeunea indica Steph. and Thysananthus minor Verdoorn are reported for Java. A determination key to the species is presented including their descriptions and illustrations.
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