Judul: Studi Konduktivitas Elektrolit Polimer Kitosan/PVA+KOH
Abstrak: The blend-based polymer electrolyte consist of chitosan and polyvinyl alcohol (PVA) as host polymers and potassium hydroxide (KOH) as the complexing salt was studied. Polymer electrolyte were obtained by the casting technique. An attempt was also made to investigate the effect of TiO2 concentration in the chitosan/PVA+KOH polymer electrolyte. The polymer electrolyte with good ionic conductivity properties were characterized by thermal analysis (DSC), FTIR, SEM, XRD and EDX. The best ionic conductivity values of 1,105 x 10-2 S cm-1 at room temperature were obtained for the sample containing 35%wt of KOH and 1,210 x 10- 2 S cm-1 for the sample containing 50% wt TiO2. The thermal analysis indicates that both glass transition temperature (75.30 °C) and crystallinity are low for chitosan/PVA+KOH 35%.
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Judul: Karakteristik Fluks Membran Kitosan  Termodifikasi Poli(Vinil Alkohol) Dengan  Variasi Poli(Etilena Glikol) Sebagai Porogen
Abstrak: Chitosan-poly(vinyl-alcohol) membrane with glutaraldehyde as cross-linked agent was classified as semi-interpenetrating network (semi-IPN) hydrogel structure. Chitosan is naturally abundant and renewable polysaccharide extracted from crustacean shells (e.g. shrimp and crab). Poly(vinyl-alcohol) or PVA is a synthetic polymer with excellent mechanical properties. Nine types of chitosan- PVA membrane were prepared from dope constituted of chitosan solution 3% (b/v), 33.30 μM glutaraldehyde 25% (v/v), and concentration of both PEG (poly(ethylene glycol)) and PVA varied from 0.0, 2.5, and 5.0%. Diluted acetic acid 1% (v/v) was used as the solvent for the dope preparation. Membrane dope was casted onto a glass plate surface and evaporated for a night at room temperature. It was then immersed in NaOH 1 M as nonsolvent for 2-3 hours. The resulting membrane was rinsed and neutralized by water and then the flux determined using destilled water (pH 7.3) and buffer phosphate pH 6 solution as feed fluids. The flux was measured at various pressure of 2.5, 5.0, 7.5, and 10.0 psi for destilled water and from 2.5 and 10.0 psi for buffer. The flux of destilled water was higher than the flux of buffer. These phenomenon showed sensitive property of hydrogel membrane upon pH environment, as the hydrogel itself was swollen in acetic condition cause reducing the membrane pore diameter. The flux decreased as PVA percentage increased, while increasing PEG percentage as the porogen increased the flux. The applied pressures was the main driving force on membrane transport and the effect on flux decreased the applied pressure increased. It was caused by compaction phenomenon occured on the matrix of membrane as related with the hydrogel structure.
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Judul: Populasi Dan Habitat Lutung Jawa (Trachypithecus Auratus) Di Cagar Alam Dungus Iwul Kabupaten Bogor
Abstrak: Cagar Alam Dungus Iwul (CADI) dengan luasan ± 9 ha merupakan salah satu habitat alami Lutung Jawa (Trachypithecus auratus). Menurut Daftar Merah IUCN status konservasi lutung jawa adalah vulnerable dan termasuk dalam daftar Appendix II CITES. Keberadaan lutung jawa di CADI sudah ada sejak tahun 1931. Hasil penelitian yang dilakukan ditemukan dua kelompok lutung jawa yaitu kelompok 1 terdiri atas 24 individu dan kelompok 2 terdiri atas 2 individu. Sex ratio individu dewasa pada kelompok 1 (1:2.67) dan pada kelompok 2 (1:1). Aktivitas harian yang paling sering dilakukan adalah makan 41%. Wilayah jelajah seluas ± 6 ha dengan jumlah sebanyak 26 individu lutung jawa.Proporsi pakan lutung jawa didominansi oleh daun sebesar 76%. Tumbuhan iwul (Orania sylvicola) merupakan tumbuhan yang paling dominan. Pohon tidur lutung jawa paling banyak menggunakan pohon pohon kihujan(Engelhardtia spicata Lesh.), asem keranji (Dialum indum L) dan kibangkong (Endiandra rubescens). Aktivitas istirahat, makan dan aktivitas sosial lutung jawa banyak dilakukan pada strata A dan B, dan aktivitas berpindah banyak dilakukan pada strata C.
Keyword: habitat, lutung jawa, populasi