Judul: Binderless particleboard made from andong bamboo and sengon wood using oxidation treatment
Abstrak: Nowadays, particleboard is manufactured using formaldehyde based adhesive as a binder. Formaldehyde emission from particleboard is a main concern in contrast to binderless particleboard (BP) which doesn’t cause such problem. The objective of this research was to find out BP production method using oxidation pretreatment. Materials used in this study were andong bamboo (Gigantochloa pseudoarundinaceae), and sengon wood (Paraserianthes falcataria) particles. The target density of BP was 0.75 g cm-3. There are five stages that have been conducted to achieve the research objective namely; determining the best pretreatment of particle, determining of optimum particle size, analyzes of oxidation time and BP characteristics correlation, determining of optimum oxidator level, and comparing BP characteristics with conventional particleboard that produced using urea formaldehyde, melamine formaldehyde, phenol formaldehyde, and isocyanate adhesives. The results indicated that BP made from particle with oxidation pretreatment performed superior characteristics compared to those of BP made from particle only with water boiling pretreatment. Oxidation pretreatment has successfully activated the chemical component of particles that indicated by changes of FTIR spectrum in wave number of 1050 cm-1 for bamboo, 1250 cm-1 and 1740 cm-1 in sengon wood, and decreasing of cellulose cristallinity in activated particles. Particle size which suitable as raw material for the manufacture of BP was particle size passes 10 mesh. Bamboo BP more sensitive on presence of fine particle compared to that of sengon BP. Oxidation pretreatment for 15 minutes was sufficient to produce BP with good physical and mechanical properties. The characteristics of the BP were similar to that of BP made of particles with a longer oxidation time in range of 15-90 minutes. Produced BP using 15%/7.5% (hydrogen peroxide/ferrous sulphate) for bamboo and 5%/5% (hydrogen peroxide/ferrous sulphate) for sengon were optimal oxidator level to produce BP and it’s have superior characteristics in term of dimensional stability and modulus of elasticity compared to those of conventional particleboard. Sengon wood more suitable as raw material for BP production compared to that of andong bamboo.
Keyword: Gigantochloa pseudoarundinaceae, Paraserianthes falcataria

Judul: Kombinasi Perlakuan Oksidasi, Penambahan Parafin dan Waktu Kempa pada Kualitas Papan Partikel tanpa Perekat dari Bambu Tali
Abstrak: Particleboard is an alternative solution of conventional boards that made from wood. Generally particleboard made with formaldehyde adhesives that have an additional negative impact on the environment due to large emissions. Binderless particleboard can be an alternative solution to replace conventional woodboard and also doesn't have a negative impact on the environment. The purpose of this research was to determine the effect of the addition of paraffin, pressing time and oxidation on the physical and mechanical properties of the medium density binderless particleboard. Bamboo particle that as material was tali bamboo (Gigantochloa apus) taken from Bogor area. Bamboo was converted to particle used a circular saw, ring flaker and screener mesh size of 20 mesh, afterwards used to make binderless particleboard with a target density of 0.4-0.9 g/cm3. The pressing conditions was 180 °C in temperature, 25 kgf/cm2 in pressure. This study was conducted with a completely randomized factorial design, where the factors studied were the addition of paraffin, pressing time and oxidation treatment. Physical and mechanical characteristics of binderless particleboard were tested according to JIS A 5908 2003. The results showed that there were significantly different from each treatment on the quality of the board. Physical and mechanical test results also showed that the binderless particleboard with oxidation treatment, addition of paraffin and pressing for 20 minutes performed the best characteristics compared with other treatments.
Keyword: pressing time, paraffin, oxidation, binderless particleboard, bamboo

Judul: Mathematical Analysis of a Cholera Spread Infection Model  Using Vaccination
Abstrak: Kolera merupakan penyakit diare yang disebabkan infeksi pada usus oleh bakteri Vibrio cholerae. Bakteri tersebut masuk ke dalam tubuh seseorang melalui makanan dan minuman yang telah terkontaminasi yang akan mengeluarkan enterotoksin di dalam tubuh seseorang pada bagian saluran usus, sehingga menimbulkan diare disertai muntah yang akut dan sangat hebat, dan berakibat seseorang dalam waktu hanya beberapa hari akan kehilangan banyak cairan dalam tubuhnya sehingga mengalami dehidrasi. Penelitian ini bertujuan untuk menganalisis model untuk penyebaran infeksi kolera menggunakan vaksinasi. Terdapat dua titik tetap, yaitu titik tetap bebas penyakit dan titik tetap endemik. Pada simulasi numerik jika nilai reproduksi dasar yakni ℛ0 < 1 maka jumlah individu yang terinfeksi akan berkurang sehingga penyakit hilang. dst.., Cholera is a diarrheal disease caused by infection of the intestine by the bacterium Vibrio cholerae. These bacteria enter a person's body through contaminated food and drink, which will release enterotoxins in a person's body in the intestinal tract, causing diarrhea accompanied by acute and very severe vomiting, and resulting in a person just in a few days of losing a lot of fluids in the body so it becomes dehydrated. This study aims to analyze a model for the spread of cholera infection using vaccination. dst ..
Keyword: fungsi Lyapunov, infeksi kolera, vaksinasi