Judul: Karakteristik Anatomi Daun Delapan Spesies Hoya spp. Bertipe Daun Non Sukulen serta Analisis Hubungan Kekerabatannya
Abstrak: Hoya spp. is epiphyte or lithophyte plant which has corolla shape like a star, usually used as ornamental plants and traditional medications. Commonly, Hoya grows in humid environment such as secondary forest, swamp, and river side. Hoya has two types of leaves in example succulent and non succulent. Leaf anatomical structure of Hoya spp. has not been widely studied, especially for the non succulent type. The aims of this research were to explore the diversity and hierarchical relationship of eight non succulent Hoya species based on leaf anatomical characters. Leaf anatomical characters were observed on the paradermal and transversal section. Anatomical data characters were analyzed using IBM SPSS version 19 program. There were individual and cluster individual stomatal, with cyclocytic type. Stomatal found at abaxial surface only (hypostomatic). Among of those, H. densifolia is the only species recorded to have adaxial and abaxial stomatal (amphistomatic). H. campanulata had the smallest stomatal size (21,6 x 17,2 μm), while H. bandaensis had the largest (28,5 x 28,5 μm). H. cilliata had the lowest stomatal density (64,6/mm2), while H. coriacea had the largest (136,7/mm2). Observation on transversal section showed that H. densifolia had the smallest leaf thickness (357,8 μm), while H. bandaensis had the largest (1075,8 μm). Based on the anatomical characters, obtained dendogram which has different hierarchychal relationship. At a distance scale of 19, showed 4 groups of kinship. Each group has specific characters. The first group has trichomes on both sides of the leaf surface. The second group has amphistomatic stomatal. The third group has between 357-536 μm thick leaves. The fourth group has between 26-28 μm abaxial stomatal width
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Judul: Evaluasi Karakter Vegetatif Hoya (Apocynaceae) di Kebun Raya Bogor
Abstrak: Hoya is epiphyte, lithophyte plant, or shrub. Information of morphological diversity is essential to it’s development as an ornamental plant. The aim of this research was to study the morphological diversity of vegetative characters of Hoya that are collected in Bogor Botanical Garden, in order to facilitate identification in the field. This research provides the diversity of vegetative characters of Hoya as one of the library reference, and provides a Hoya identification key based on vegetative characters. Twenty six Hoya species were morphologically characterized their vegetative organs. The data then were tabulated, and used for constructing an identification key. The results showed that Hoya has variation in several vegetative characters i.e shape, size, base and tip of the leaf, vein shape of leaf, leaf blade surface (indumentum), leaf blade color, petiole shape, indumentum, size and color of the stem. The best characters for distinguishing among Hoya species were the form of the leaf blade and leaf venation. Some species have some unique characters that can be used to distinguish among species of Hoya, for example H. imbricata has imbricate leaf arrengement, reniform shape and purple abaksial surface. The leaf venation of H. finlaysonii is pinnate that has contrast color between venation and blade. The specific features of other species will be discussed further in this paper.
Keyword: identification key, vegetative characters, morphology, Hoya

Judul: Sintesis dan uji aktivitas katalitik Fe3O4 dari campuran limbah wire plating sludge dan FeSO4 pada efisiensi pembakaran batu bara
Abstrak: Combustion catalyst is an additive added to the fuel to increase the heat energy released. Fe3O4 was the combustion catalyst used in this study, synthesized from PT Sumiden Cibinong wire plating sludge waste by coprecipitation between FeCl3 from wire plating sludge and FeSO4. Synthetic Fe3O4 was characterized by using Faurier transform infrared spectrophotometer, X-ray diffractometer, and atomic absorption spectrophotometer. The Fe2O3, Fe2O3+Fe3O4, and Fe3O4 catalysts were dispersed separately with oil, surfactant, and water. The catalyst mixed into coal having 4596 cal/g calorific value, with overall concentration of catalyst mixture in the coal was 0.01%(w/w). The combustion activity resulted by differential thermal analyzer showed an increase of combustion fficiency of 91.0% with Fe2O3 catalist, whereas addition of Fe3O4 catalyst decreased the efficiency of 55.6%.
Keyword: catalyst, coal, Fe3O4, wire plating sludge.