Judul: Potensi Bioplastik Berbasis Pati Kulit Singkong dengan Pengisi Selulosa Sabut Kelapa berdasarkan Studi Literatur
Abstrak: Bioplastik merupakan jenis plastik yang mampu didegradasi oleh mikroorganisme. Tujuan penelitian ini adalah memperoleh pati kulit singkong dan selulosa sabut kelapa sebagai bahan baku bioplastik. Kulit singkong dipilih sebagai bahan baku karena memiliki kandungan pati yang tinggi. Rendemen pati kulit singkong segar yang dihasilkan pada penelitian ini mendekati 25%. Pengisi berupa selulosa sabut kelapa digunakan untuk memperbaiki sifat mekanik bioplastik dengan rendemen mendekati 15%. Penelitian ini dilanjutkan dengan studi literatur untuk mengevaluasi sifat mekanik bioplastik berbasis pati dengan pengisi selulosa. Hasilnya mengungkapkan bahwa kuat tarik bioplastik komposit pati-selulosa cenderung lebih tinggi dibandingkan tanpa selulosa. Pemanjangan bioplastik tersebut cenderung lebih rendah sedangkan hidrofobisitas cenderung lebih tinggi dibandingkan dengan bioplastik tanpa selulosa. Studi ini juga mengungkapkan bahwa interaksi yang terjadi antara pati dan selulosa merupakan interaksi fisik yang ditandai dengan tidak terciptanya gugus fungsi baru pada spektrum inframerah.
Keyword: bioplastik, kulit singkong, pati, selulosa

Judul: Potensi Bioplastik Berbasis Pati Biji Nangka dengan Selulosa Sabut Kelapa sebagai Material Pengisi
Abstrak: Bioplastik berbasis pati biji nangka dengan material pengisi selulosa sabut kelapa merupakan salah satu upaya pengendalian dan pemanfaatan limbah untuk mengatasi masalah plastik. Penelitian ini bertujuan membuat bioplastik dari pati biji nangka dengan material pengisi selulosa sabut kelapa, serta memprediksikan sifat bioplastik yang dihasilkan dan potensi pengembangannya. Kadar pati pada biji nangka adalah 30.23% dengan kadar air sebesar 2.09%, sedangkan rendemen selulosa dari sabut kelapa sebesar 31.14% dengan kadar air sebesar 1.97%. Bioplastik secara kasat mata berwarna putih dengan komponen selulosa yang tersebar merata, permukaan sedikit kasar, dan relatif kaku. Kajian terhadap hasil penelitian terdahulu menunjukan bahwa, bioplastik dengan bahan-bahan yang digunakan pada penelitian ini berpotensi untuk dikembangkan menjadi bioplastik kemasan dengan densitas tinggi. Penambahan selulosa pada bioplastik ini diprediksi meningkatkan kuat tarik, memperbaiki permukaan penampang, mampu menurunkan nilai pemanjangan, dan menurunkan daya serap air. Bioplastik yang dihasilkan dihubungkan dengan interaksi fisik.
Keyword: bioplastik, pati biji nangka, selulosa sabut kelapa

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite