Judul: Pembuatan dan Karakterisasi Biokomposit Klobot Jagung dan LLDPE dengan Metode Hot Press
Abstrak: The research has been made biocomposites cornhusk and Linear Low Density Polyethylene (LLDPE) with hot press method. Biocomposites made with the variation of cornhusk:LLDPE are 30:70, 40:60, 50:50, 60:40, 70:30, and it is characterized of the mechanical characteristics (tensile and tear) with Universal Testing Machine (UTM), biodegradation in a qualitative manner and morphology by Scanning Electron Microscopy (SEM). Cornhusk are also analyzed the thermal characteristics with Differential Scanning Calorimetry (DSC), a functional groups by Fourier Transform Infrared (FTIR) and morphological analyzed by SEM. Mechanical analysis showed the mechanical characteristics decrease with the addition of cornhusk concentration on biocomposites, and concentration 30:70 has the highest mechanical characteristics with tensile strength 24.77 MPa, elongation 19.10% and tear strength 53.94 N/mm. The result is contrast with the biodegradable analysis in which the bigger concentration cornhusk then the level of biodegradability is higher. The result of mechanical analysis also supported by the analysis of morphology biocomposites and LLDPE. Analysis of a functional groups and morphology cornhusk showed that cornhusk had the high fibers with transition glass cornhusk at 196.21 oC.
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Judul: Pengaruh Variasi Komposisi LLDPE dan Klobot Jagung Terhadap Karakteristik Mekanik Dan Biodegradasi Mulsa Bioplastik
Abstrak: Mulsa Bioplastik ini merupakan campuran polimer Linear Low Density Polyethylene (LLDPE) dan klobot jagung ukuran 200 mesh dengan metode calandering, variasi 5%, 10%, dan 15% klobot jagung. Biomulsa plastik yang telah dicetak dengan calandering, dianalisis mikrostruktur, sifat mekanik (uji tarik) dan biodegradasi. Analisis proksimat menunjukkan klobot jagung memiliki kadar serat dan karbohidrat tinggi. Konsentrasi 5% klobot jagung memiliki sifat mekanik paling tinggi dengan kekuatan tarik arah persilangan 8.598 MPa dan arah mesin 20.75 MPa, strain at break arah silang 143.3% dan arah mesin 409%. Hasil uji biodegradasi memperlihatkan Aspergillus niger dapat tumbuh pada biomulsa plastik, tetapi Penicillium sp. terlihat tidak tumbuh pada biomulsa plastik. Proses biodegradasi tersebut menyebabkan adanya persen berat yang hilang pada biomulsa plastik.
Keyword: biodegradable, klobot jagung, mulsa bioplastik, sifat mekanik

Judul: Pengaruh vaksinasi terhadap dinamika populasi pada model SIR (Susceptible-Infected-Recovered)
Abstrak: SIR model can be used to model the spread of diseases in a closed population based on certain assumptions. In this research, the SIR model is formulated by including the factor of vaccination. As the result, the model has been shown to have two equilibrium points, i.e. disease free and endemic equilibrium. A simulation study is carried out to illustrate the model. The results show that some equilibrium points are asymptotically stable. Moreover, a minimum level of vaccination has been defined. For the vaccination level less than the minimum level, increase in the vaccination level results in decrease of the proportion of infected individuals in the corresponding equilibrium point. On the other hand, for the vaccination level greater than the minimum level, increase in the vaccination level results in decrease the proportion of susceptible individuals in the corresponding equilibrium point. Furthermore, when vaccination level is greater than the minimum level, it is found that the time needed for the disease to extinct is shorter.
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