Judul: The Addition of Niobium (Nb) to Uranium Zirconium (U-Zr) Alloy for Nuclear Fuel
Abstrak: Pengembangan bahan bakar nuklir merupakan aspek penting dalam teknologi reaktor nuklir, dengan fokus pada keamanan dan ekonomi. Saat ini, reaktor riset G.A. Siwabessy menggunakan bahan bakar uranium silisida (U3Si2/Al) yang memiliki beberapa kekurangan, seperti densitas maksimum 4,80 gU/cm, The development of nuclear fuel is a crucial aspect of nuclear reactor technology, focusing on safety and economics. Currently, the G.A. Siwabessy research reactor uses uranium silicide (U3Si2/Al) fuel, which has drawbacks, such as a maximum density of 4.80 gU/cm
Keyword: zicronium, reactor, niobium, nuclear, ?-uranium

Judul: Separation of Neodymium from U3Si2/Al Fuel Plate for Burn-Up Determination
Abstrak: Neodymium is a common fission product produced in nuclear fission reactions. Neodymium in this study was chosen as a burn-up indicator for U3Si2/Al fuel element plates because the neodymium isotope is a stable fission product with a fairly high yield. Some procedures were carried out to separate neodymium, starting with the separation of cesium isotopes (137Cs, 134Cs) through the precipitation method, then separation of uranium isotopes (235U, 238U) and plutonium isotopes (239Pu, 238Pu) with Dowex 1x8 ion exchange resin, and separation of neodymium (Nd), samarium (Sm), as well as cerium (Ce) with Dowex 1x4 ion exchange resin. The Cs recovery reached 99.95%. The U and Pu isotopes resulting from the separation are subjected to an electrodeposition process and the weight of each isotope can be measured with an alpha spectrometer. The separation results of Nd from Sm and Ce have been proven using an XRF spectrometer. The neodymium isotopes separation was corrected using the standard addition method, and an average total Nd content of 2.4 ppm was obtained in the PEB U3Si2/Al bottom solution. It is hoped that this separation method can be applied in determining burn-up of nuclear fuel.
Keyword: neodymium, burn-up indicator, U3Si2/Al fuel plate

Judul: Pola Distribusi Penyu Lekang (Lepidochelys olivacea) Berdasarkan Struktur Genetik di Teluk Cendrawasih, Pulau Kapoposang, dan Kupang.Pola Distribusi Penyu Lekang (Lepidochelys olivacea) Berdasarkan Struktur Genetik di Teluk Cendrawasih, Pulau Kapoposang, dan Kupang.
Abstrak: The olive ridley sea turtle (Lepidochelys olivacea) is one species of sea turtles that can be found in Indonesia. The distribution pattern of olive ridley turtle (Lepidochelys olivacea) based on the genetic structure is poorly known. Therefore, this study aimed to determine the distribution pattern of olive ridley sea turtle (Lepidochelys olivacea) based on the genetic structure Mitochondrial. DNA Cytochrome Oxidase 1 (CO1) was used as marker. The distribution pattern indicated that the absence of inter-population genetic structure of olive ridley turtle (Lepidochelys olivacea) between three populations of Cendrawasih Bay, Kapoposang Island, and Kupang (FST=-0.023;P-value=0.462). High genetic diversity was observed in three populations (h=1.00+/-0.04). High gene flow seems influenced by the behavior of turtle migration. The olive ridley turtle migration patterns moving within the Indonesian waters.
Keyword: Lepidochelys olivacea, DNA Barcoding, genetic structure, migration