Judul: Karbonisasi Nano Serat Selulosa Asetat dari Kapas yang Dibuat Dengan Metode Electrospinning
Abstrak: Cellulose content of cotton is 94%. The high value cellulose content of cotton makes the extraction cellulose in cotton will be easier. One method to making nano fiber that is electrospinning technique. Electrospinning method can produce nano fibers at a flow rate 1 ml/h, but at flow rate 1.75 ml/h and 2.5 ml/h produce nano spheres based on images of SEM. After carbonized of sample graphite formed, based on XRD data visible from the highest peak in the 2θ is 26.2o which is the typical peak of Graphite Carbon based on the data pattern JCPDS No. 41-1487. EDX results showed that the carbonized result containing 90.10% carbon and 9.9% oxygen. Previously cellulose containing 47.49% Carbon, 48.40% Oxygen and 4.11% gold which was the result of the coating for sample preparation for SEM. While the FTIR results are unreadable due to carbonization change in the sample which makes the previous sample is polar to non-polar. Based on the results generated LCRmeter sample after carbonized is a good conductor.
Keyword: Bogor Agricultural University (IPB), XRD, graphite, FTIR, electrospinning, cotton

Judul: Sintesis Nanofiber Kitosan/Polyethylene Glicol (PEG)/Polyvinyl Alcohol (PVA) dengan Metode Electrospinning
Abstrak: Teknologi nano sekarang ini telah menjadi daya tarik para peneliti di dunia. Teknologi ini mempunyai arti dan manfaat yang sangat penting karena hal tersebut dapat menciptakan penghematan ruang, bahan baku, proses produksi, energi dan sekaligus akan meminimalkan limbah dan pencemarannya. Salah satu bidang nanoteknologi yang sedang banyak dikembangkan adalah pembuatan nanofiber. Salah satu aplikasi serat nano (nano fiber) adalah tekstil medik berbentuk non-woven mats yang biokompatibel, luas area yang tinggi, dan ukuran pori kecil (30–150 Å), scaffold pada rekayasa jaringan, wound dressing dan kapsul pada drugs delivery system. Penelitian ini membuat serat nano dari bahan kitosan, PEG dan PVA dengan metode electrospinning. Karakterisasi yang dilakukan yaitu uji viskositas, hasil dari uji viskositas menunjukkan bahwa larutan dengan PEG 10% mempunyai nilai viskositas tertinggi. FTIR untuk menentukan gugus fungsi yang terbentuk pada serat, uji mekanik dengan melakukan uji tarik agar mengetahui tegangan tarik dari serat nano yang dihasilkan. Uji ketebalan untuk mengetahui tebal serat nano yang dihasilkan. Karakterisasi SEM untuk mengetahui morfologi serat nano yang dihasilkan dari metode electrospinning. Hasil karakterisasi menunjukkan konsentrasi PEG 10% menghasilkan serat nano yang paling baik.
Keyword: Electrospinning, Kitosan, PEG, PVA

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