Judul: The Jatropha Hulls (Jatropha curcas L.) as an Alternative Raw Material of Particle Board
Abstrak: Jarak pagar (Jatropha curcas Linn) selain dikenal oleh masyarakat sebagai tanaman obat ternyata juga merupakan tanaman potensial penghasil BBM alternatif pengganti solar, atau disebut biodiesel. Berkaitan dengan pengembangan jarak pagar sebagai bahan baku BBN (Bahan Bakar Nabati), maka potensi pemanfaatan hasil ikutan (by-product) pada pengolahan jarak pagar perlu mendapat perhatian karena berpotensi menghasilkan produk-produk yang bermanfaat bagi manusia. Kulit buah jarak pagar merupakan salah satu hasil ikutan (by-product) pada pengolahan jarak pagar yang tidak dimanfaatkan lagi dalam proses pengolahan minyak, sehingga perlu diolah lebih lanjut menjadi produk yang memiliki nilai guna. Kulit buah jarak pagar (Jatropha curcas Linn) merupakan salah satu bahan berlignoselulosa yang memiliki potensi sebagai bahan baku papan partikel. Penelitian ini bertujuan untuk mengetahui sifat fisis dan mekanis papan partikel kulit buah jarak pagar dan pengaruh perlakuan variasi kadar perekat terhadap kualitas papan partikel. Bahan yang digunakan adalah kulit buah jarak pagar, adapun jenis perekat yang digunakan adalah perekat phenol formaldehida (12%, 14% dan 16%) dengan kerapatan target adalah 0,7 g/cm3. Pada penelitian pendahuluan perekat yang digunakan adalah perekat urea formaldehida (10%, 12% dan 14%) dan Standar pengujian yang digunakan adalah standar JIS A 5908 (2003). Hasil penelitian menunjukkan bahwa papan partikel yang menggunakan perekat phenol formaldehida mampu meningkatkan kestabilan dimensi dan sifat mekanis papan apabila dibandingkan dengan papan partikel yang menggunakan perekat urea formaldehida. Berdasarkan hasil pengujian secara keseluruhan, maka sifat fisis dan mekanis papan partikel kulit buah jarak pagar belum sesuai dalam pemanfaatannya sebagai bahan baku konstruksi. Sehingga masih perlu dilakukan upaya peningkatan sifat-sifat papan partikel tersebut. Semakin tinggi kadar perekat yang ditambahkan pada papan partikel maka sifat mekanis yaitu kekuatan lentur, keteguhan patah, keteguhan rekat dan kuat pegang sekrup akan semakin meningkat, sedangkan untuk sifat fisis kadar air, daya serap air dan pengembangan tebal cenderung menurun.
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Judul: Karakterisasi kulit buah jarak (Jatropa curcas L) dan pemanfaatannya sebagai bahan baku papan pertikel berkualitas
Abstrak: Jatropha fruit hulls (JFH) is a waste resulted from biodiesel process and its used only as compos materials. According to fiber proportion and chemical composition, JFH had a potency for using as raw materials of particleboard manufacturing. However, the acidity properties of JFH caused problem in UF resin curing, so that resulting inferior bonding strength of board. Adjusting of acidity and controlling of pressing temperature and time were expected to solve those problem. The objective of this research was to obtain the best condition to produce high quality particleboard made of JFH and UF resin. This research consist of five steps. The first step was to analyse of materials characteristic of JFH and UF resin included of pH, buffering capacity, chemical component, chemical compound, wettability, solid content, viscosity, and gelatine time. Suitability indicator between of JFH and UF was determined by extractive content, pH, and wettability. Second step was to analyse of particle immersing treatment (immersing in cold water for 24 hours, hot water for 1 hours, and 1% acetic acid solution) to physical and mechanical properties of particleboard. Third step was to analyse of pressing temperature and time to obtain optimum pressing condition in particleboard manufacturing. The fourth step was to analyse of wood shaving (mangium wood) and wood veneer (sengon and jabon wood) to reinforce of mechanical properties of particleboard. The last step was to analyse of non wood particle (bamboo and sorghum stalk) to reinforce of mechanical properties of particleboard. The result showed that JFH had alkali properties, it was caused by alkaline from several chemical compound that composed of JFH i.e ammonium bicarbonate, mercaptomethane, guaiacol, 2,6-dimethoxyphenol dan cyclopropyl carbinol. Immersing treatment was reducing of extractive content, pH and increased of JFH wettability. Furthermore, those parameter used as indicator to determine of lignocellulosic materials compatibility with UF resin to result the best quality of particleboard. Based on technical and efficiency considering, immering treatment in cold water for 24 hours, hot water for 1 hour, and 1% acetic acid solution were selected for particleboard manufacturing. The best properties of particleboard was resulted by JFH immersing treatment in acetic acid solution. The exploration of pressing temperature and time to obtain of the best pressing condition was expected for optimizing of UF resin polymerization. Hot pressing in 130 0C temperature for 10 minute resulting the best properties of particleboard, but the thickness swelling and modulus of elasticity value were not fulfill of JIS A 5908 (2003). The reinforcement method by strong materials were expected of resulting the improvement of mechanical properties. JFH and wood shaving mixture, overlaid with wood veneer, JFH and non wood particle mixture resulted to improve of physical and mechanical properties especially of MOE and MOR value. The overlaid with sengon and jabon veneer, and JFH and bamboo acid treated mixture was increasing of MOE and MOR value. The overlay technique by veneer and JFH and bamboo acid treated mixture resulting MOE value that fulfill of JIS A 5908 (2003). Based on this reseach had resulted of recomendations included of immersing in 1% acetic acid solution, hot pressing at
Keyword: Extractive, particle acidity, jatropha fruit hulls, particleboard, urea formaldehyde resin

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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