Judul: Karakteristik Kimia Serat Buah Kapuk sebagai Bahan Penyerap Minyak
Abstrak: Kapok fiber (Ceiba pentandra) are naturally hydrophobic and oleophilic fiber that would be usefull for oil adsorbent. This research examined of chemical composition, oil sorption capacity and its selectivity of natural and ethanolbenzene extracted fibers. Kapok fibers were taken from Madura-East Java, Pati- Central Java, and Bogor-West Java. Based on the chemical composition, kapok fibers contained holoselulosa 83.04-84.16%, alfa-selulosa 37.43-40.26%, lignin klason 13.24-16.25%, etanol-benzena solubility 1.02-1.17%, cold water solubility 0.63-0.77%, hot water solubility 4.14-4.62% and NaOH 1% solubility 19.49- 26.47%. Adsorption capacity of natural kapok fiber was in range of 30.70 to 63.20 g/g fiber, while extracted kapok fibers exhibited oil adsorption of 26.62 to 50.74 g/g fibers. Dissolution of oleophilic extractives substances seemed that was responsible for lower oil adsorption capacity. Naturally, kapok fiber has a very high selectivity to adsorb oil than that of water, therefore kapok fibers could be promoted as an oil adsorbent material with a high selectivity in the oil-water system.
Keyword: kapok fibers, oil adsorption, oleophilic, hydrophobic, chemical components

Judul: Karakterisasi Berbagai Jenis Buah Kelapa (Cocos nucifera L.)
Abstrak: Tanaman kelapa hibrida merupakan tanaman yang tinggi produksi buahnya. Pada beberapa kasus, buah kelapa hibrida justru menghasilkan "rubber copra" dan minyak yang mengandung resin. Hal ini selain akan mempersulit proses ekstraksi, juga menyebabkan "loss" minyak selama pemurnian minyaknya. Selain sebagai bahan baku minyak kelapa, daging buan kelapa juga dapat diolah menjadi Kelapa parut kering dan santan awet. Pada prinsipnya kualitas produk yang dihasilkan sangat ditentukan oleh karakteristik bahan bakunya. Tujuan penelitian ini adalah untuk menginventari- sası karakteristik berbagai jenis buah kelapa (Cocos nucifera L.) untuk keperluan perencanaan dan pengem- bangan industri. Buah kelapa yang diamati meliputi kelapa dalam Tenga (DTA-1 dan DTA-2), kelapa dalam Bali (DBI), kelapa dalam Lokal (LOKAL), kelapa hibrida KHINA-1, KHINA-2, KHINA-3, serta kelapa hibrida MAHA, NYDXWAT dan PB-121. Pengamatan yang dilakukan meliputi Karakteristik daging buah, kopra, minyak kelapa, kelapa parut kering, testa, angka konversi buah dan kekentalan santan. Rancangan percobaan yang digunakan adalah ran- cangan acak lengkap dengan eksperimen faktor tunggal. Dari hasil pengamatan ternyata daging buah paling tebal justru diperoleh dari kelapa dalam LOKAL. Selain itu diperoleh kadar air daging buah yang sama pada se- mua sampel yang diamati. Pengamatan komposisi kimia Kopra menunjukkan bahwa buah kelapa hibrida PB-121, NYDXWAT dan MAHA bukan merupakan sumber karbohidrat. Kopra yang "non-rubbery" diperoleh dari DTA-1 dan KHINA-3, yang angka kekerasan kopranya juga tergolong tinggi. Berdasarkan standar mutu perdagangan, 90% sam- pel menghasilkan kopra berkadar lemak standar mutu I, sedangkan kelapa dalam LOKAL hanya menghasilkan kopra mutu II..dst
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Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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