Judul: Papan Partikel Pelepah Kelapa Sawit Menggunakan Perekat Urea Formaldehida (UF) dan Asam Sitrat
Abstrak: Pelepah sawit sebagai hasil limbah padat perkebunan sawit merupakan sumber bahan berlignoselulosa yang sangat potensial untuk dijadikan bahan baku produk komposit salah satunya yaitu papan partikel. Papan partikel merupakan produk papan komposit atau panel kayu yang dikembangkan agar efisiensi bahan baku meningkat dengan pemanfaatan bahan berlignoselulosa lainnya. Penelitian ini bertujuan menghasilkan papan partikel yang ramah lingkungan dengan mengevaluasi perbedaan konsentrasi perekat urea formaldehida (UF) dengan asam sitrat terhadap sifat fisis dan sifat mekanis papan partikel pelepah kelapa sawit. Papan dibuat menggunakan faktor konsentrasi perekat UF dan asam sitrat dengan taraf 100:0, 75:25, 50:50 dan dikempa pada suhu 140 °C selama 10 menit dengan target kerapatan 0,8 g/cm . Karakteristik papan diuji secara fisis dan mekanis yaitu kerapatan, kadar air, daya serap air, pengembangan tebal, keteguhan lentur, keteguhan patah, dan keteguhan lentur berdasarkan standar SNI 03-2105-2006. Hasil uji fisis dan mekanis papan menunjukkan bahwa papan dengan konsentrasi perekat UF dengan asam sitrat komposisi 50:50 memiliki hasil paling baik.
Keyword: asam sitrat, pelepah kelapa sawit, papan partikel, urea formaldehida, citric acid, palm fronds, particle board, urea formaldehyde

Judul: Papan Partikel Dari Pelepah Kelapa Sawit Menggunakan Perekat Asam Sitrat dan Molase
Abstrak: Pelepah kelapa sawit merupakan biomassa kelapa sawit yang biasanya tidak dimanfaatkan secara optimal, pelepah kelapa sawit memiliki kandungan lignoselulosa yang berpotensi untuk dijadikan papan partikel dan ketersediannya yang cukup melimpah.Penelitian ini bertujuan menghasilkan papan partikel yang ramah lingkungan tanpa menggunakan bahan kimia berbahaya. Selain itu, menganalisis pengaruh kadar perekat dengan menggunakan asam sitrat dan molase terhadap karakteristik sifat fisis dan mekanis papan partikel. Papan dibuat dengan kerapatan target 0,8 g/cm³ dan ukuran 30 x 30x 0,6 cm menggunakan kempa panas suhu 200°C selama 10 menit dengan tekanan 5 Mpa. Pengujian sifat fisis dan mekanis papan partikel mengacu pada standar SNI 03-2105-2006 (kerapatan, kadar air, daya serap air, pengembangan tebal, MOE, MOR, dan keteguhan rekat). Hasil penelitian ini menunjukan kadar perekat berpengaruh nyata terhadap karakteristik sifat fisis dan mekanis papan partikel Semakin tinggi kadar perekat yang ditambahkan mampu meningkatkan sifat fisis dan mekanis pada papan plafon yang dibuat., Palm fronds are palm biomass that is usually not used optimally, palm fronds have lignocellulose content that has the potential to be used as a particleboard and its availability is quite abundant. This study aims to produce environmentally friendly particle boards without the use of harmful chemicals. In addition, it analyzes the effect of adhesive levels using citric acid and molasses on the characteristics of the physical and mechanical properties of particle boards. The board was made with a target density of 0,8 g/cm³ and a size of 30 x 30x 0,6 cm using a heat felt of 200°C for 10 minutes with a pressure of 5 Mpa. Testing of the physical and mechanical properties of particle boards refers to the standard SNI 03-2105-2006 (density, moisture content, water absorption, thickness swelling, MOE, MOR, and internal bounding). The results of this research show that the adhesive content has a significant effect on the characteristics of the physical and mechanical properties of composite ceiling boards. The higher the adhesive content added is able to improve the physical and mechanical properties of the ceiling board made.
Keyword: adhesive content, citric acid, molasses, palm fronds, particle board

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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