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: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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