Judul: Production of Cellulose Acetate Films from Non-Wood Source in Indonesia: Theoretical Study
Abstrak: Lignocellulose is a type of polysaccharide consists of cellulose, hemicellulose, and lignin that forming in plants. Wood consumption in the world always increasing but areal planting is decreasing. Material from non-wood is required because it’s very abundant and renewable natural resource. Cellulose acetate is derivative product from cellulose is very important in industry. This study aims to determine the potential production of cellulose acetate films from non-wood materials in Indonesia and to identify raw materials that have the potential to produce cellulose acetate films. The methodology for this study using collection of data needed to conduct an analysis of the potential production of cellulose acetate films was carried out in the territory of Indonesia. Cellulose acetate and each production from cotton stalk, sorghum straw, sugarcane bagasse, rice husk, and Oil Palm Empty Fruit Brunch (OPEFB) have different methods. Every cellulose acetate has different each production from different journals to get best result. The data for cellulose acetate films was analyzed by several characteristics such as the production process, yield and Degree of Substitution (DS), Fourier Transform Infrared (FTIR), and mechanical properties. This study explains utilization from non-wood resources which is abundant in Indonesia can be an alternative besides using wood., Lignoselulosa merupakan salah satu jenis polisakarida yang terdiri dari selulosa, hemiselulosa, dan lignin yang terbentuk pada tumbuhan. Konsumsi kayu di dunia selalu meningkat namun areal tanam semakin berkurang. Bahan dari non kayu dibutuhkan karena sumber daya alamnya yang sangat melimpah dan terbarukan. Selulosa asetat merupakan produk turunan dari selulosa yang sangat penting dalam industri. Penelitian ini bertujuan untuk mengetahui potensi produksi film selulosa asetat dari bahan non kayu di Indonesia dan mengidentifikasi bahan baku yang berpotensi menghasilkan film selulosa asetat. Metodologi penelitian ini menggunakan pengumpulan data yang diperlukan untuk melakukan analisis potensi produksi film selulosa asetat yang dilakukan di wilayah Indonesia. Selulosa asetat dan setiap produksi dari kapas, jerami sorgum, ampas tebu, sekam padi, dan Tandan Kosong Kelapa Sawit (TKKS) memiliki metode yang berbeda. Setiap selulosa asetat memiliki produksi yang berbeda dari jurnal yang berbeda untuk mendapatkan hasil yang terbaik. Data film selulosa asetat dianalisis dengan beberapa karakteristik seperti proses produksi, rendemen dan Derajat Substitusi (DS), Fourier Transform Infrared (FTIR), dan sifat mekanik. Studi ini menjelaskan pemanfaatan sumber bukan kayu yang melimpah di Indonesia dapat menjadi salah satu alternatif selain pemanfaatan kayu.
Keyword: cellulose acetate films, non-wood materials, characteristics of cellulose acetate

Judul: Kajian Penggunaan Selulosa Mikrobial Sebagai Bahan Baku Pembuatan kertas
Abstrak: Paper refers to thin mass of felted sheet separated from water suspension of prevalently cellulose-based pulp fiber on a fine screen, followed by sheet forming, compression, drying and finishing action. Paper and paper products are widely used as printing and writing media, packaging material and other varieties of functions. World consumption of paper steadily increases at 3,05 % per year, while in Indonesia the yearly consumption in the last five years (i.e 2002 – 2006) recorded an average increase at 2,8%. Consequently, this calls for intensive use of cellulose-based materials. In general, the raw material for pulp and paper comes from woods, due to their more secured continuity-supply and favorable properties or characteristic. Conversely, this situation can enchanc the rate of forest destruction (deforestation) from which the woods are obtained. Nowadays, deforestation rate tends to increase uncontrollably along with increasing-demand for woods and their derived products, including pulp and paper. Such alarming deforestation can exert negative impacts on the environment, among which is global warming. The global warming further will affect climate change radically and natural disasters (e.g. floods, erosion, storms, and hurricanes). The use of wood for pulp, paper, and other celullose based products reveals several weaknesses, among others, high energy consumption and catastrophic environmental pollution caused by the use of chemical substances for the delignification (lignin dissolution) process during wood pulping, which harmful to human beings and other living creatures. Another set back is the low productivity of wood for the supply of cellulose (i.e. polymer containing glucose units) compared to the cutting rotation of the tree growth to provide wood, which takes a long time and bring about concerns related to environmental issues. This unfavorable situation demand the seeking of other cellulose alternatives, which can expectedly substitute for or lessen the reliance on wood materials for pulp and paper manufacturing. One of the favorable alternatives is the microbial cellulose synthesized biologically from particular biomass materials potential as glucose source, using particular types of microorganisms (i.e. bacteria) among other Acetobacter species. The microbial cellulose afford remarkable advantage over the conventional wood derived sellulose, such as high level purity (free from lignin and hemicellulose), the easy isolation of the process, and exerting high cellulose crystallinity as well as its productivity. This entails an immense potency of raw material for microbial cellulose in an attempt to overcome the difficulty in procuring the conventional wood based cellulose materials for pulp and paper.
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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