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: Karakteristik Anatomi Daun beberapa Spesies Hoya spp. Bertipe Daun Sukulen serta Analisis Hubungan Kekerabatannya
Abstrak: Hoya (Hoya spp.) is an epiphyte or lithophyte vine or shrub. Hoya’s flower has beautiful unique shape and it is considered as original plant from Southeast Asia and surroundings. This plant has two type of leaf, succulent and non succulent. Succulent plant can adapt well in extreme condition, especially in dry period. Anatomy characters can be used to identify, classify, and determine plant relationship. The aims of this research were to identify anatomical character of succulent Hoya’s leaf and to determine their relationship. Ten exmined species Hoya spp. (H. diversifolia, H. latifolia, H. dolichosparte, H. bilobata, H. lacunosa, H. verticillata, H. purpureofusca, H. kuhlii, H. oblanceolata, and H. micrantha) showed anatomical similarity which was epidermal layer, hipodermal, mesophil, and the absence of sponge tissue at mesophil. However there were many diversities between specieses. Based on paradermal section of the leaf, stomata was only found on the abaxial side and have two type, individual stomata and both individual and stomatal cluster. Hoya diversifolia had the smallest stomatal size, while Hoya latifolia had the biggest. Hoya lacunosa had the lowest stomatal density, while Hoya bilobata had the highest. Hoya diversifolia, Hoya lacunosa, and Hoya oblanceolata had the lowest stomatal index, while Hoya bilobata had the highest. Observation on transversal section showed that Hoya purpureofusca had the lowest leaf thickness, while Hoya kuhlii had the highest. The hierarchical cluster analysis based on anatomical leaf character showed different patterns of relationship which diversed as three groups at relationship scale 15.
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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.