Judul: Model prediksi awal musim hujan di Pulau Jawa dengan menggunakan informasi suhu muka laut di kawasan Pasifik dan India
Abstrak: The rainfall variability is one of an important role to play onset of wet season. This research aims to analyze that SST (Sea Surface Temperature) exerting an influence on rainfall onset over Java. The significant scale (15°S – 15°N; 80°E- 100°W) of SST patterns are observed to derive a potential predictor rainfall onset over Java. The onset wet season is define as the first 10-day that receive at least 50 mm followed by 2 consecutive 10-days. In Java generally it starts from 1 September. In this study, The regression Multivariate method was offered to develop a rainfall onset model prediction based on SST circulation patern. The principal component and regression technique are improved to achieve a better models and cross validation technique were applied to validate models. Domain predictor of models were derived using spatial correlation analysis result between Rainfall onset data each ZOM over Java and SST anomaly from Indian Ocean to Pacific Ocean during 1978-2007 . There are 28 from 30 ZOM which have potential predictors that be trained to models. The high spatial coherence of the rainfall onset is SST pattern at Juni-Juli-August that represent SST on eastern equatorial Pacific as characteristic of El Nino Southern Oscillation (ENSO), SST on Western Sumatera Island as characteristic of Indian Ocean Dipole Mode (IOD) and SST on around Java region as Characteristic of local condition. Three representative correlation patterns of Java Rainfall onset with SST Indian-Pacific area are investigated that clarify of ENSO, IOD and local condition. Verification result for those models showed promising skill prediction during test in year of 2008 with standart deviation 10 days. In Java generally, skill prediction when rainfall onset advanced exhibited better result than skill prediction when it delayed. The Indonesian ocean area that has local characteristic have influenced better rainfall onset over Java than others. It indicated that models which developed using predictor of Indonesian SST have better skill prediction than SST of Indian or pacific ocean area. However, predictor which has combination domain area of Indonesian SST and Pacific have main influenced rainfall onset over Java. It can be explained that 18 ZOM’s model have been using predictor from those domain.
Keyword: 

Judul: Prediksi Awal Musim Hujan di Pulau Jawa berdasarkan Indeks Variabilitas Iklim
Abstrak: Southern Oscilation (ENSO), El Nino Modoki, Indian Ocean Dipole (IOD) dan Sea Surface Temperature (SST) sekitar Jawa serta Madden Julian Oscillation (MJO) yang dominan memengaruhi AMH di Jawa (2) menyusun model prediksi AMH di Jawa berdasarkan indeks variabilitas iklim yang dominan tersebut. Model persamaan AMH disusun menggunakan model regresi linier dan skill model prediksi dievaluasi menggunakan Relative Operating Characteristics (ROC). Selain itu, dilakukan validasi menggunakan data yang tidak dilibatkan dalam penyusunan model. Hasil penelitian menunjukkan bahwa ENSO (indeks anomali SST Nino 3.4) dapat menjelaskan sebagian besar variabilitas AMH di Jawa. Oleh karena itu, ENSO bulan Juli dan Agustus dapat digunakan sebagai prediktor dalam menyusun model persamaan AMH. Model persamaan yang disusun berdasarkan indeks tersebut mempunyai skill yang baik. Rata-rata skill model prediksi mencapai 84% (ENSO bulan Juli) dan 76% (ENSO bulan Agustus) untuk AMH maju dari normal dan 83% (ENSO bulan Juli) dan 86% (ENSO bulan Juli) untuk AMH mundur dari normal.
Keyword: AMH, ENSO, Jawa, MJO, ROC

Judul: Sintesis dan Pencirian Kompleks Fe(III)-Kuersetin
Abstrak: Quercetin belongs to flavonols which is able to chelate metal ions. Quercetin may chelate metal ions at 3’,4’-catechol, 3- or 5-hydroxycromone sites. In this study, quercetin was complexed with Fe(III). The complex with Fe(III) ions from FeCl3·6H2O was more stable than the complex derived from Fe(NO3)3·9H2O. The quercetin was yellow in color and showed maximum wavelengths (λ􀭫􀭟􀭶) at 250 and 370 nm. The Fe(III)-quercetin complex from Fe(NO3)3·9H2O was yellowish green with 􀟣􀭫􀭟􀭶 at 280 and 420 nm, whereas that from FeCl3·6H2O was dark green with 􀟣􀭫􀭟􀭶 at 280 and 430 nm. The 􀟣􀭫􀭟􀭶 shift indicated that the complex was formed at 3-hydroxychromone site. The Fe(III)- quercetin complex was formed with 1:1 metal-ligand mole ratio based on atomic absorption spectrophotometry analysis and the X-ray diffractogram showed that the crystallinity of the complex was 37%.
Keyword: