Judul: Sintesis Perisai Neutron Berbasis UHMWPE
Abstrak: Telah dilakukan sintetis Ultra High Molecule Weight Poly-Ethylene sebagai perisai radiasi neutron thermal. Eksperimen dilakukan dengan meletakkan sumber radiasi neutron di depan perisai dengan variasi tebal serbuk UHMWPE 0.22 cm, 0.34 cm, 0.50 cm, 0.85 cm, 0.96 cm, dan 1.1 cm; tebal padatan UHMWPE 0.70 cm, 1.03 cm, 1.49 cm, 1.83 cm, 2.25 cm, dan 4.52 cm; serta tebal campuran antara UHMWPE dengan resin 0.50 cm, 1.01 cm, 1.19 cm, 1.40 cm, 1.58 cm, dan 1.70 cm.. Hasil penelitian menunjukkan bahwa nilai koefisien atenuasi memiliki karakteristik fungsi eksponensial terhadap tebal perisai (x, cm) yaitu untuk serbuk UHMWPE 0.555, padatan UHMWPE 0.189, serta campuran UHMWPE dengan resin sebesar 0.422. Nilai koefisien atenuasi terbesar terdapat pada bahan serbuk UHMPWE, kemudian campuran UHMWPE dengan resin, dan padatan UHMWPE.
Keyword: koefisien atenuasi, neutron, perisai radiasi, resin, UHMWPE

Judul: Sintesis dan Simulasi Kinerja Perisai Radiasi Nuklir Terhadap Paparan Sinar-x/Sinar Gamma dan Berkas Neutron
Abstrak: Telah dilakukan sintesis dan simulasi komposit beton sebagai perisai sinarx/ sinar gamma dan neutron. Sampel yang digunakan sebagai perisai sinarx/ gamma yaitu Beton+Baja Paduan, Beton+Co, Beton+Mn, Beton+Cr, dan Beton kontrol tanpa filler dengan variasi ketebalan masing-masing 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, dan 12 mm. Hasil uji eksperimen dan simulasi perisai sinar-x/sinar gamma menunjukkan bahwa Beton+Baja Paduan memiliki kinerja paling baik dalam menahan radiasi. Koefisien atenuasi linier Beton+Baja Paduan hasil simulasi menggunakan energi foton 0.03295 MeV yaitu 3.8568 cm-1, menggunakan energi foton 0.04295 MeV yaitu 1.8794 cm-1, dan eksperimen yaitu 2.3884 cm-1. Sampel perisai neutron terdiri dari Beton+B4C 6%, Beton+B4C 12%, Beton+B4C 18%, dan Beton kontrol tanpa filler dengan variasi ketebalan masingmasing 3 mm, 5 mm, dan 7 mm. Koefisien atenuasi linier yang didapatkan berturut-turut yaitu 2.6590 cm-1, 3.8822 cm-1, 4.0029 cm-1, 0.1151 cm-1. Beton+B4C 18% memiliki kemampuan terbaik dalam menahan radiasi neutron termal.
Keyword: Beton, Neutron, Perisai radiasi, Sinar Gamma, Sinar-X

Judul: Populasi dan Habitat Kakatua-Kecil Jambul-Kuning di Bentang Alam Mbeliling Bagian Barat, Kabupaten Manggarai Barat, Nusa Tenggara Timur
Abstrak: Cacatua sulphurea parvula or yellow-crested cockatoo were spread distributed at Sunda Kecil Archipelago, Nusa Tenggara, except at Sumba Island. This species amount in the nature is very small, caused by the illegal hunting and trading. The purpose of this research is to get the information about population and habitat of the cockatoo in Flores, especially at the western part of Mbeliling Landscape. Cocatoo census was conducted by look-down method at vantage points when cockatoo flew passed by. Habitat analysis was carried out with vegetation analysis. The census showed that there were two groups of cockatoo, consisted of 69 cockatoos in Tao hill and 15 cockatoos in Nggoer River. Flight pattern of each group ranged 0-100 meters above the sea level and crossed mangrove forest, savanna, monsoon forest and cultivation plant vegetation. The vegetation analysis resulted Ceiba petandra or silk-cotton tree as the tree that most used by cockatoo and had the highest TIV (Tree Importance Value), 47,48%. Cockatoo’s foods which observed were crown flower (Calotropis gigantea), and Moringa olifera. The population of Cockatoo which observed at western part of Mbeliling Landscape was estimated came from Rinca Island, Komodo National Park. It can be concluded that the location might be only used by rhe cockatoo came from Rinca Island as their daily exploration area for foraging.
Keyword: habitat., ecology, population, Flores, Cacatua sulphurea parvula