Judul: Pengoptimuman ekstraksi dan fase gerak kromatografi lapis tipis untuk pemisahan komponen seledri
Abstrak: Pengoptimuman fase gerak pada kromatografi lapis tipis (KLT) dan kondisi ekstraksi merupakan salah satu cara mendapatkan pemisahan komponen yang baik dan sebagai langkah awal analisis sidik jari. Kondisi ekstraksi perlu dioptimumkan terlebih dahulu untuk mengisolasi komponen kimia dari tanaman obat dengan jumlah yang maksimum dengan membandingkan dua teknik ekstraksi (maserasi dan sonikasi), kemudian dianalisis dengan fase gerak optimum. Validasi metode seperti stabilitas, spesifisitas, presisi, dan ketangguhan digunakan agar dapat mengidentifikasi seledri secara cepat dan terpercaya. Kombinasi pelarut yang dapat menghasilkan profil pemisahan komponen seledri dengan baik adalah kloroform:diklorometana dengan nisbah 75:25. Teknik ekstraksi terbaik untuk mengisolasi komponen kimia pada seledri dalam waktu yang relatif singkat ialah ekstraksi sonikasi. Kondisi optimum ekstraksi sonikasi berdasarkan rancangan central composite adalah pada waktu ekstraksi 10 menit, bobot sampel 0.8726 g, dan volume pelarut 1.59 mL pada deteksi ultraviolet 366 nm. Semua kriteria validasi metode dapat diterima sehingga dapat digunakan untuk mengidentifikasi seledri.
Keyword: Seledri, Kromatografi lapis tipis, Fase gerak, Analisis sidik jari, Bogor Agricultural University, Institut Pertanian Bogor, IPB

Judul: Analisis Sidik Jari Kromatografi Lapis Tipis Rimpang Kencur (Kaempferia galanga).
Abstrak: RAFI. Tumbuhan obat mengandung beragam senyawa kimia yang dapat menyulitkan upaya pengendalian mutu untuk menunjukkan ciri spesifiknya. Analisis sidik jari kromatografi lapis tipis (KLT) dapat menghasilkan pola pemisahan multikomponen yang khas bagi setiap tumbuhan. Oleh karena itu penelitian ini bertujuan mengembangkan analisis profil sidik jari KLT rimpang kencur (Kaempferia galanga) untuk kendali mutu. Ekstrak dipisahkan menggunakan pelat silika gel F254 sebagai fase diam, pelarut kloroform:toluena (9:1) sebagai fase gerak dapat memisahkan 11 pita pada sinar ultraviolet 366 nm. Senyawa etil p-metoksisinamat dipilih sebagai penciri dan terdeteksi pita berwarna ungu pada sinar tampak (RF = 0.85) setelah derivatisasi menggunakan larutan asam sulfat 10% (v/v). Validasi metode menghasilkan pola pemisahan ekstrak rimpang kencur stabil dalam kromatografi, pada pelat dan larutan selama 3 jam serta secara visualisasi. Spesifitas menghasilkan pita berwarna ungu (RF = 0.85) pada profil rimpang kencur yang identik dengan senyawa penciri. Uji presisi dan presisi antara menunjukkan keterulangan pola pemisahan dengan selisih nilai RF masing-masing 0.00-0.01 dan 0.00-0.02. Uji ketegaran menunjukkan hasil yang baik terhadap penurunan jarak pengembangan dan perubahan jenis bejana kromatografi.
Keyword: analisis sidik jari, etil p-metoksisinamat, Kaempferia galanga, KLT

Judul: The Effects of Variance of Interest rate to Variance of Annuity Future Values
Abstrak: Time value of money is a concept that refers to the difference of the value of money due to time difference. The value of money for present time would not be the same as the value of money in the future. The value of money for present time is called as Present Value (PV) of the money and the value of money for future time is called Future Value (FV) of the money. Determination the value of money, for present and future time, depends on the time and rate of return. The value of money is determined by several factors such as inflation, fluctuation of interest rates, and government policy in securities and taxation. Due to fluctuation of the value of money we need a FV formulation, it is useful for knowing whether an investment can be profitable or not, and this information is useful also in budget analysis. Annuity is defined as a series of payments made for a specific period. The payment, fixed or varied, can be made at the beginning or at the end of the period. Annuity paid at the beginning of the period is called annuity-due and annuity paid at the end of the period is called immediate annuity-certain. The accumulated value of the annuity after few years later is called as a final value or a future value. Burnecki et al. (2003) have discussed about the FV of a fixed-rate annuity in which payments are made according to the arithmetic or geometric series. They have also examined FV for annuities in which payments are made according to arithmetic or geometric series with random rates of interest. This paper examines FV for annuity-due in which payments are made according to arithmetic or geometric series with interest rates as a random variable, which is normal distribution ,  . Future value formula is expressed in recursive form. FV for annuity-due which payments are made according to the arithmetic or geometric series with random rates of interest is calculated by theoretical way and simulation way. The random rates of interest is denoted as k k i  i  , where k i an independent random variable; i is a constant and k  is a random variable which has normal distribution ,  . By using the determined parameters, a sequence of random rates of interest are generated for theoretical calculation. Meanwhile for the simulation, the random rates of interest is generated 1000 times for the simulation. The generated data give mean value, variance, and standard deviation. Moreover, error of mean value, variance, and standard deviation from the theoretical and simulation results are calculated. Error calculation uses Symmetric Mean Absolute Percentage Error (SMAPE). The smaller the value of SMAPE is the more accurate the simulation. The interest rate variances are varied from 0.000036 to 0.0001 to study the relationship between variance of rates of interest and variance of future value. The theoretical and simulation results show that when the variance of random rates of interest increases, then the variance of FV increases linearly. FV of the annuity-due in
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