Judul: Penggunaan bahan adsorben dan pengkelat pada proses pemurnian minyak kayu putih (Melaleuca leucadendron Linn) Kabupaten Buru
Abstrak: Penelitian ini terdiri atas dua tahap yakni penelitian pendahuluan dan penelitian utama. Penelitian pendahuluan dilakukan untuk mengetahui karakteristik bahan baku, jenis dan konsentrasi bahan pemurnian yang akan digunakan pada penelitian utama berdasarkan nilai kejernihan paling tinggi. Pengujian karakteristik bahan baku berdasarkan SNI MKP tahun 2006 meliputi pengujian fisiko-kimia (warna, bau, bobot jenis, indeks bias, kelarutan alkohol, putaran optik, dan sineol), nilai kejernihan, dan kandungan logam. Dari hasil yang didapatkan, secara umum karakteristik fisikokimia minyak kayu putih telah memenuhi SNI tersebut kecuali pada uji warna dan kandungan sineol. Berikut ini adalah data karaktersitik bahan baku yang digunakan yakni warna (hijau bening), bau (khas MKP), bobot jenis (0,9235), indeks bias (1,468), kelarutan dalam etanol 70% (1:6 jernih), putaran optik (-0,8°), kandungan sineol (40,73%), dan nilai kejernihan (81,30%). Uji kadar logam yang dilakukan meliputi kadar Cu, Fe, dan Mg dengan nilai masing-masing adalah 18,16 mg/l, 8,76 mg/l, dan 0,300 mg/l. Bahan-bahan pemurnian yang digunakan pada penelitian pendahuluan ini adalah tiga jenis bahan pengkelat (Asam Sitrat, Asam Tartarat, dan EDTA) dan tiga jenis bahan adsorben (Bentonit, Zeolit, dan Arang Aktif) dengan konsentrasi masing-masing bahan yang digunakan adalah 2%. Berdasarkan nilai kejernihan yang didapatkan, asam sitrat dan bentonit merupakan bahan pemurnian yang baik dengan nilai kejernihan (% transmitan) masing-masing adalah 99,95% dan 99,4%. Kedua jenis bahan ini digunakan sebagai bahan pemurnian pada penelitian utama dengan konsentrasi masing-masing yang digunakan terdiri atas empat konsentrasi, yakni 0%, 1%, 2%, dan 3%. Pengamatan yang dilakukan pada penelitian utama adalah rendemen, pengujian fisiko-kimia sesuai SNI 06-3954-2006, kadar logam, dan kejernihan, dst
Keyword: Bogor Agricultural University, Institut Pertanian Bogor, IPB, Purification, Cajuput oil, Citric acid, Bentonite

Judul: Penggunaan Bahan Adsorben dan Pengkelat Pada Proses Pemurnian Minyak Kayu Putih (Melaleuca leucadendron Linn.) Kabupaten Buru
Abstrak: Purification is one of method to improve the quality of cajuput oil. This study aims to identify and analyze the effect of citric acid and bentonite using to the yield, limpidity, metal content, and Buru cajuput oil quality based on SNI 06-3954-2006 (scent, color, specific gravity, index of refraction, optical rotation, and solubility in 70% ethanol). Variable process conditions studied were type of material purification (citric acid and bentonite) and their concentration were 0%, 1%, 2%, and 3%. The citric acid and bentonite using had an affect on yield, specific gravity, optical rotation and hadn’t an in with a limpidity and index of refraction based on statistical tests were performed using the SAS (Statistical Analysis System). Despitefully, citric acid using produced oil have been resulted on tranparent until greenish yellow colored, whereas the use of bentonite have produced oil that it is yellowed. The scent of cajuput oil hasn’t changed after the purification process. The best treatment was selected based on the value of limpidity, it was a purification treatment using 1% citric acid. Three types metals content (Cu, Fe, and Mg) decreased after purification using 1% citric acid. Other that, the content of cineol increased after purified from 40.73% to 43.82%. The results of refining oil by using citric acid and bentonite have meet in accordance with the ISO (2006).
Keyword: 

Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model