Judul: Ketersediaan Pakan antar Kelompok Simakobu (Simias concolor) di Hutan Peleonan, Siberut Utara, Kepulauan Mentawai
Abstrak: The endemic primate Simakobu (Simias concolor) in Mentawai is endangered due to habitat decreases. The purpose of this study was to discover the availability of food trees in the home ranges of two groups of Simakobu, Aldran group and Aldo group. Each of them consists of a different number of group members. Although Aldran group has more group members, Aldo group’s home ranges is 0,4 Ha wider than Aldran’s. However, the variety of food trees in Aldran’s home range is 11.8 % higher than Aldo’s. There are 113 species of trees inventoried in Peleonan forest and 53 types of which are food sources of Simakobu. Coccoseras borneensis is the most dominant food tree available in the both regions. Simakobu’s preferences are the young leaves and fruits. In general, the food abundance and variety in both home ranges are still adequate. The less varied food trees available in Aldo’s area and the group composition are expected to be the driving factors that made Aldo group explores more and eventually has a wider home range.
Keyword: the availability of food tree, Simias, simakobu, Siberut, Mentawai Islands

Judul: Studi Ko-Habitasi Antara Simakoru (Simias concolor) dan Joja (Presbytis potenziani) di Area Siberut Conservation Program (SCP), Pulau Siberut-Kepulauan Mentawai Sumatera Barat
Abstrak: Siberut Island represented union of various endemic and unique plant and animal as effect of continually evolution process. One of uppermost example is four species of rndemic primate found in this island Both of Simakobu (Simias concolor) and Joja (Presbytis potenziani) representing some of endemic primates exploiting Siberut Island as habitat and lived at some habitat during more than hundred of year. Putman (1984) uttered that two or more species with some or similiar ecology eill not earn to coexist in same community. Therefore, This research is very attractive and requiared to be conducted in order to knowing habitat exploiting concept among Simakobu (Simias concolor) and Joja (Presbytis Potenziani). The aims of this research are: 1) Knowing pattern of location of activities according to dimension of space by Simakobu and Joja. 2) Knowing niche breadth quantitatively using by Simakobu and Joja. 3)Knowing overlapping niche among Simakobu and Joja
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Judul: Characterizations of low alloy steel sae 4422  plated with chromic acid (Cro3)
Abstrak: Characterizations of low alloy steel SAE 4422 plated with chromic acid (CrOrO3) was use Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), RD),Energy Dispersive Analysis of X-Ray (EDAX), Hardness Test and Roughness Test. Microstructures analysis exhibits cracks and grain boundaries microcracks as a characteristics of chrome metal found at plating metal. Perlite and Ferrite as grains of steel found at base metal with grain boundaries around it. Phase analysis of plating metal appropriate to chrome metal with lattice constant (a) is 2.559 Å and phase analysis of base metal appropriate to iron ferrite with lattice constant (a) is 3.318 Å. Both plating and base metal have cubic system. Chemical analysis of plating metal at surface section exhibits that cracks area have highest value of carbon element compare with grains and grains boundaries area. While chemical analysis of base metal at cross section exhibits that perlite have highest value of carbon element compare with ferrite and grain boundaries. The hardness value of plating metal at surface section and cross section are 753 and 637 VHN. While, the hardness value of base metal and interface area at cross section are 205 and 373 VHN. The roughness value at measurement points of chrome surface for as received sample are 0.445 μm. Observation used Optical Microscopy and Scanning Electron Microscopy exhibits surface irregularities combine to form surface texture of plating metal at surface section.
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