Judul: Adsorpsi Asam Lemak Bebas dan Zat Warna Biru Metilena Menggunakan Campuran Selulosa Kayu Sengon-Zeolit
Abstrak: Limbah minyak goreng bekas dan zat warna dari berbagai macam industri merupakan penyebab pencemaran di Indonesia. Tujuan penelitian ini adalah melakukan adsorpsi asam lemak bebas dari minyak goreng bekas dan zat warna biru metilena menggunakan selulosa hasil isolasi kayu sengon dan zeolit yang diaktivasi secara asam, menentukan kondisi optimum adsorpsi, serta menentukan isoterm adsorpsi dan kinetika adsorpsi. Percobaan yang digunakan adalah metode tumpak. Kondisi yang dioptimisasi meliputi bobot, waktu, dan nisbah dari kedua adsorben. Kondisi optimum adsorpsi asam lemak bebas didapatkan pada bobot 1 gram, dengan nisbah adsorben 3:1 pada selulosa:zeolit, dan waktu adsorpsi selama 60 menit. Kondisi optimum zat warna biru metilena didapatkan pada nisbah adsorben 1:3 untuk selulosa:zeolit pada waktu 10 menit. Adsorpsi asam lemak bebas dan biru metilena mengikuti isoterm Freundlich. Adsorpsi asam lemak bebas dan biru metilena mengikuti kinetika reaksi orde dua semu.
Keyword: adsorption, adsorption kinetics, cellulose, free fatty acid, methylene blue, zeolite

Judul: Adsorpsi asam lemak bebas dan zat warna menggunakan campuran kaolin-limbah padat tapioka
Abstrak: Adsorption of free fatty acids in used cooking oil and methylene blue dye is studied. The results showed that the mixture of kaolin and tapioca solid waste is a potential adsorbent for the adsorption free fatty acids and dyes. The effect of kaolin activation treatment, such as heating temperature and the use of acid is also studied. The best activation results for the kaolin activation used in the free fatty acid adsorption was heating treatment at 750 °C followed by treatment with H2SO4 30%, whereas for methylene blue adsorption by acid treatment only. Activation of tapioca solid waste was using 30% H3PO4 treatment. Optimum conditions for adsorption, adsorption capacity, and adsorption efficiency of a mixture of kaolin and tapioca solid waste showed different results and specific for each type of sample used. For the same amount of adsorbent, free fatty acid adsorption was reached in 90 minutes using the ratio of activated kaolin and tapioca solid waste of 25:75 (1:3). Meanwhile, methylene blue adsorption was achieved at 30 minutes with the ratio of activated kaolin and tapioca solid waste of 75:25 (3:1). The results showed that the type of adsorption isotherm for free fatty acids was Freundlich isotherm, whereas for methylene blue adsorption was Langmuir isotherm.
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Judul: Implementation of Spatio-Temporal Change Query in Relational Database.
Abstrak: Geographic object changes in various views. Object changes are recorded using a model of static storage. No historical connection between old version data and new version data has been built. For that, a storage model of spatio-temporal queries that can analyze spatio-temporal changes has been developed. The object changes the geometry are grouped according to the taxonomy of Spatio-Temporal Pattern Change. This research has been able to apply the query patterns change including born, expand, merge, contract, split, normal and die. This query based on geometric (area) changes. The implementation of spatio-temporal change queries represents an object changes continuously with easy, change detection is done by comparing two versions of data. Keyword: spatio-temporal change query, spatio-temporal change pattern.
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