Judul: Study of Growth and Flowering of Several Indonesian Hoyas (Hoya sp.) Indonesia
Abstrak: Indonesia merupakan negara mega-biodiversity dengan banyak keanekaragaman hayati. Hoya menjadi salah satu kekayaan milik Indonesia dari famili Apocynaceae yang secara alami tumbuh merambat di bawah naungan hutan tropika. Banyaknya spesies hoya belum semuanya diikuti dengan kelengkapan informasi mengenai siklus hidup dan pembungaan, maupun cara budidaya yang optimal. Penelitian ini bertujuan untuk menambah informasi mengenai masa pertumbuhan vegetatif dan generatif hoya, serta morfologi dan anatomi daun hoya. Penelitian dilaksanakan di greenhouse Kebun Percobaan Leuwikopo dan Laboratorium Mikroteknik Program Studi Agronomi dan Hortikultura pada Desember 2022 hingga Juli 2023. Pengumpulan informasi dilakukan melalui tahap pengamatan dan pengukuran dengan parameter vegetatif berupa panjang batang, jumlah batang, jumlah daun, jumlah buku, dan parameter generatif berupa jumlah kuntum bunga, diameter cabang, dan periode pembungaan, serta parameter morfologi dan anatomi daun berupa bentuk daun, bentuk pangkal dan ujung daun serta keberadaan jaringan epidermis, dan jaringan mesofil. Hasil yang didapatkan menunjukkan perbedaan pertumbuhan vegetatif maupun generatif tiap spesies hoya, terutama pada kecepatan tumbuh dan durasi munculnya bunga. Perbedaan juga ditemukan pada bentuk, tipe dan struktur anatomi daun hoya., Indonesia is a mega-biodiversity country with rich biodiversity. Hoya, a member of the Apocynaceae family, is one of tropical epiphytic vines naturally growth under tropical forest. The existing species of hoya not accompanied by complete information regarding the life cycle and flowering yet, as well as optimal cultivation methods. This study aims to add information on the vegetative and generative growth stages of hoya, as well as the morphology and anatomy of its leaves. The research was conducted at the greenhouse of Leuwikopo Experimental Farm and the Microtechnic Laboratory of the Department of Agronomy and Horticulture from December 2022 to July 2023. Data collected by observation and measurement, encompassing vegetative parameters such as branch length, number of branches, number of leaves, and number of nodes, and generative parameters including number of flower buds, branch diameter, and flowering period. Additionally, morphological and anatomical parameters of the leaves, such as leaf shape, base and tip shape, and the existence of epidermal and mesophyll tissues were recorded. The results revealed variations in the vegetative and generative growth among different species of hoya, especially in growth speed and duration of flower appearance. The differences are also found in the shape, type and anatomical structure of hoya leaves.
Keyword: anatomi, generatif, hoya, morfologi, vegetatif

Judul: Morphological characterization of Hoya diversifolia Blume growing spontaneously in Bogor Botanical Garden
Abstrak: Hoya diversifolia merupakan tumbuhan epifit yang tumbuh subur pada berbagai inang dengan karakter batang berkulit tebal, kasar, dan retak– retak. Penelitian ini bertujuan untuk mengkarakterisasi tumbuhan H. diversifolia dan menyeleksi tumbuhan H. diversifolia terbaik yang tumbuh spontan di Kebun Raya Bogor untuk dikembangkan sebagai tanaman hias. Karakterisasi dilakukan terhadap karakter kualitatif dan kuantitatif organ vegetatif dan generatif dari 30 individu H. diversifolia. Selanjutnya data ditabulasikan dalam bentuk matrik dan digunakan untuk membangun dendogram dengan index RT (Rogers and Tanimoto) dan metode UPGMA. Hoya diversifolia bervariasi pada warna dan ukuran bunga, daun, dan batang. Berdasarkan karakter kualitatif dan kuantitatif, ditemukan individu H. diversifolia yang berpotensi dikembangkan sebagai tanaman hias. Individu ini memiliki sembilan pedunkel dengan rata- rata 18 pedicel disetiap pedunkel., Hoya diversifolia is an epiphytic plant that thrives on various of host stem with thick-skinned, rough, and cracked character. This study aimed to characterize H. diversifolia plants and selecting the best plants that grow spontaneously in the Bogor Botanical Garden to be developed as an ornamental plant. Morphological characterization of qualitatif and quantitative characters was observed from vegetative and generative organs of 30 individuals of H. diversifolia. Furthermore, the data were tabulated and used to construct a dendogram using index RT (Rogers and Tanimoto) and UPGMA method. H. diversifolia varied in color and size of flowers, leaves, and stems. Based on qualitative and quantitative characters, there was an individual of H. diversifolia potentially to be developed as an ornamental plant. This variant had nice peduncle with 19 pedicel each peduncle. Keywords: Hoya diversifolia Blume, Morphology, Bogor Botanical Garden
Keyword: Hoya diversifolia Blume, morfologi, Kebun Raya Bogor

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