Judul: Development of Fire Retardant Lignin Based From Palm Oil Biomass for Composite Tile Applications
Abstrak: Penghambat api (fire retardant) digunakan untuk menghambat atau memperlambat fase utama dari api yang berkembang. Lignin merupakan salah satu bahan penghambat api yang dapat dikompositkan dengan bahan lain untuk mendapatkan sifat tertentu tanpa menurunkan sifat tahan api pada lignin sendiri. Selulosa yang sudah berukuran nano memiliki sifat yang dapat memberikan penguatan yang baik, sifat penghalang gas dan stabilitas thermal yang baik. Keunggulan tersebut diharapkan dapat menjadikan nano fibrilasi selulosa (CNF) sebagai penguat lapisan lignin dan menambah stabilitas thermalnya pada lapisan yang akan di aplikasikan pada papan genteng komposit. Penelitian ini bertujuan untuk meningkatkan nilai ketahanan api pada papan genteng komposit dari sorghum dengan beberapa metode pengaplikasian komposit tahan api. Metode ini menggunakan satu faktor dengan 3 taraf yaitu pengaplikasian komposit tahan api (laminasi, mix, coating). Komposit tahan api (lignin-CNF-Bentonite) mengalami peningkatan suhu degradasi dibandingkan dengan lignin komersial. Pada papan genteng komposit yang di lapisi dengan metode laminasi dan coating cenderung mengalami peningkatan sifat mekanik, fisis dan tahan api., Fire retardants are used to retard or slow down the main phases of a developing fire. Lignin is a fire retardant material that can be composited with other materials to obtain certain properties without reducing the fire retardant properties of the lignin itself. Cellulose Nano-fibril has properties that can provide good reinforcement, gas barrier properties and good thermal stability. These advantages are expected to make Cellulose Nano-fibril (CNF) reinforcement of the lignin layer and increase its thermal stability in layers that will be applied to composite tile boards. This study aims to increase fire resistance value on composite tile boards from sorghum with several methods of applying fire retardant composites. This method uses one factor with 3 levels, namely the application of fire-resistant composites (lamination, mix, coating). Refractory composites (lignin-CNF-Bentonite) experienced an increased degradation temperature when compared to commercial lignin. Composite tile boards which are coated with the lamination and coating methods tend to experience an increase in mechanical, physical and fire retardant properties.
Keyword: biomassa kelapa sawit, Ketahanan api, lignin, nano fibrilasi selulosa

Judul: Lignin and Lignosulfonates from Eucalyptus Black Leachate to Increase the Fire Resistance Properties Particle Boards from Areca
Abstrak: Lignin berpotensi sebagai aditif Flame Retardant (FR) yang ramah lingkungan karena dapat memanfaatkan limbah dan berasal dari bahan terbarukan. Lignin bersifat tidak larut air, sehingga diperlukan modifikasi melalui proses sulfonasi menjadi lignosulfonat agar mudah dalam pengaplikasiannya. Lignin dan lignosulfonat dari kayu Eukaliptus diaplikasikan pada papan partikel pelepah pinang berperekat asam sitrat-sukrosa. Penelitian ini bertujuan menganalisis pengaruh penambahan lignin dan lignosulfonat sebagai aditif terhadap sifat ketahanan api dan fisis mekanis papan partikel pelepah pinang berperekat asam sitrat-sukrosa. Lignin dan lignosulfonat dari kayu Eukaliptus diaplikasikan pada papan partikel pelepah pinang berperekat asam sitrat-sukrosa. Pengujian papan partikel meliputi uji ketahanan api, sifat fisis dan mekanis. Hasil penelitian menunjukkan bahwa kehilangan berat papan partikel setelah diuji bakar torch menurun setelah ditambahkan lignin dan lignosulfonat. Penambahan larutan lignin dan lignosulfonat tidak berpengaruh signifikan terhadap sifat ketahanan api papan partikel setelah diuji dengan UL-94. Pengujian sifat fisis mekanis papan partikel yang mengacu pada standar Japanese Industrial Standards (JIS) A 5908-2003 menunjukkan bahwa penambahan lignosulfonat meningkatkan sifat fisis dan mekanis papan partikel walaupun secara keseluruhan belum memenuhi standar JIS A 5908-2003., Lignin has the potential as an environmentally friendly Fire Retardant (FR) additive in biocomposite manufacturing. Lignin is water-insoluble, which requires modification of the solubility through a sulfonation process to become lignosulfonate for easy application. Lignin and lignosulfonates from Eucalyptus wood were applied as filler to the areca nut frond particleboard bonded citric acid-sucrose. This research aims to analyze the effect of adding lignin and lignosulfonate as additives on the fire resistance and mechanical-physical properties of the areca nut frond particleboard with citric acid-sucrose adhesive. Particleboard testing includes fire resistance tests and physical and mechanical properties. The results showed that the weight loss of particle board after the torch-burning test decreased after adding lignin and lignosulfonate. The addition of lignin and lignosulfonate solutions did not have a significant effect on the fire resistance properties of particleboard after being tested with UL-94. Testing of the physical and mechanical properties of particle board referring to the Japanese Industrial Standards (JIS) A 5908-2003 standard shows that the addition of lignosulfonate improves the physical and mechanical properties of particle board even though overall it does not meet the JIS A 5908-2003 standard.
Keyword: lignin, lignosulfonate, particleboard, fire retardant

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model