Judul: Gliserolisis RBDPO (Refined Bleached Deodorized Palm Oil) dengan Lipase untuk Sintesis MDAG (Mono-Diasilgliserol)
Abstrak: Indonesia adalah negara produsen minyak sawit terbesar didunia, untuk itu perlu dilakukan diversifikasi produk yang dapat meningkatkan nilai ekonomi kelapa sawit. Salah satu produk berbasis kelapa sawit yang potensial untuk dikembangkan adalah emulsifier monodiasilgliserol (MDAG). MDAG adalah emulsifier yang paling banyak digunakan dalam industri pangan. Diperkirakan kebutuhan dunia akan MDAG setiap tahunnya berkisar antara 132.000 ton. Sintesis MDAG secara enzimatis mulai banyak diteliti karena dalam prosesnya membutuhkan lebih sedikit energi, memiliki selektifitas katalis dan kemurnian serta kualitas produk yang dihasilkan lebih tinggi. Tujuan dari penelitian ini adalah untuk mengoptimalkan produksi MDAG melalui proses gliserolisis secara enzimatis.
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Judul: Sintesis Mono-Diasilgliserol Dari Refined Bleached Deodorized Palm Oil Dengan Metode Gliserolisis Skala Laboratorium
Abstrak: Produksi minyak sawit di Indonesia sangat melimpah. Sebagian besar diolah menjadi refined bleached deodorized palm oil (RBDPO) dan sisanya diekspor ke beberapa negara. Salah satu produk yang memiliki prospek yang baik untuk meningkatkan nilai tambah RBDPO adalah mono-diasilgliserol (MDAG). MDAG merupakan emulsifier sintesik yang paling banyak digunakan di industri pangan. Salah satu cara untuk mensintesis DMAG adalah melalui proses gliserolisis yaitu dengan mereaksikan triasilgliserol (TAG) dengan gliserol. Penelitian ini bertujuan untuk mendapatkan kondisi reaksi proses sintesis MDAG (waktu reaksi dan konsentrasi katalis) yang sesuai dengan metode gliserolisis skala laboratorium dengan menggunakan bahan baku RBDPO dan gliserol, menggunakan katalis NaOH serta mengetahui karakteristik fisik dan kimia MDAG yang dihasilkan. Tahapan yang dilakukan pada penelitian ini diawali dengan karakterisasi bahan baku RBDPO, sintesis MDAG, analisis data dan karakterisasi produk MDAG. Proses sintesis MDAG skala laboratorium menggunakan bahan baku RBDPO dan gliserol dengan perbandingan 1:2.3 dengan waktu reaksi 120 menit dan 180 menit serta konsentrasi katalis 0.50%, 0.75% dan 1.00%. Produk MDAG dapat diperoleh dari kombinasi perlakuan waktu reaksi 180 menit dan konsentrasi katalis 0.5% dan 0.75%. Kondisi tersebut menghasilkan MDAG dengan persentase fraksi monoasilgliserol 45.77%, diasilgliserol 27.46%, dengan titik leleh 45-46°C, kadar asam lemak bebas 2.34% dan kadar gliserol bebas 19.04% pada konsentrasi katalis 0.5% serta persentasi fraksi monoasilgliserol 47.78%, diasilgliserol 28.05%, kadar asam lemak bebas 3.97% dan kadar gliserol bebas 16.61%.
Keyword: emulsifier, gliserolisis, mono-diasilgliserol, RBDPO

Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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