Judul: Degradasi Pewarna Azo oleh Lakase yang Terimobilisasi pada Matriks Tunggal PVA-Alginat dan Perlit
Abstrak: Pewarna azo dicirikan dengan adanya gugus kromofor dan gugus lainnya, seperti gugus aromatik dan turunan benzena yang menyebabkan pewarna ini susah untuk didegradasi, sehingga menjadi penyebab pencemaran lingkungan. Tujuan penelitian ini adalah menganalisis kemampuan lakase asal jamur WM01 (Cymatoderma dentriticum) yang terimobilisasi pada matriks berbeda (PVAalginat dan perlit) dalam melakukan dekolorisasi salah satu pewarna azo, yaitu Reactive Black 5 (RB 5). Hasil penelitian mengindikasikan bahwa lakase yang diekstrak dari jamur WM01 berhasil melakukan dekolorisasi pewarna RB 5 dalam bentuk bebas dan terimobilisasi. Lakase terimobilisasi dapat melakukan dekolorisasi lebih banyak pewarna pada aktivitas yang rendah (0.36 U/L) dibandingkan dengan bentuk bebasnya. Lakase yang diimobilisasi pada matriks yang berbeda akan menghasilkan tingkat dekolorisasi yang berbeda, yang dipengaruhi oleh kereaktifan matriks, perbedaan perlakuan saat preparasi, dan penambahan mediator enzim. Tingkat dekolorisasi tertinggi didapatkan dari proses dekolorisasi pewarna RB 5 oleh lakase yang terimobilisasi pada matriks perlit Tipe A.
Keyword: dekolorisasi pewarna, perlit, PVA-alginat, mobilisasi, lakase

Judul: Uji Keberadaan Amina Aromatik Hasil Biodegradasi Zat Warna Azo
Abstrak: Masuknya zat warna azo ke dalam lingkungan menjadi masalah yang serius. Dalam lingkungan, zat warna azo dapat mengalami biodegradasi mengbasilkan amina aromatik. Senyawa yang tidak berwarna ini bersifat toksik, mutagenik, dan karsindgenik terhadap hewan dan man usia. Selain itu polaritas amina aromatik menyebabkan amina aromatik banyak dijumpai di perairan. Dalam penelitian dilakukan analisis amina aromatik dalam sampel Orange II yang didegradasi oleh jamur Penicillium sp L2A dan dari air limbah pabrik tekstil. Sebagai standar am ina aromatik digunakan 1- naftilamina. Amina aromatik diderivatisasi menjadi senyawa iodo turunannya melalui reaksi azotasi yang diikuti dengan reaksi substitusi. Senyawa hasil derivatisasi yang diperoleh kemudian dianalisis menggunakan kromatografi gas dengan detektor ionisasi nyala.
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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