Judul: Pembuatan Hidrogel Nanofiber Selulosa dari Tandan Kosong Kelapa Sawit (TKKS)
Abstrak: Serat selulosa telah berhasil diisolasi dari tandan kosong kelapa sawit (TKKS) melalui proses delignifikasi menggunakan larutan KOH 6% selama 12 jam, kemudian dilanjutkan dengan proses bleaching menggunakan hipoklorit selama 5 jam. Berdasarkan uji ADF NDF, selulosa yang didapatkan memiliki kadar selulosa 69,55%, hemiselulosa 17,76%, dan lignin 5,81%. Selanjutnya nanofiber diisolasi dari selulosa melalui proses mechanical treatment. Gambar SEM menunjukkan bahwa ukuran nanofiber selulosa yang berhasil diisolasi adalah ± 30 nm. Nanofiber selulosa tersebut kemudian dibentuk menjadi hidrogel menggunakan proses vacum filtration dan alkaline treatment. Hidrogel yang dihasilkan menunjukkan bentuk yang lebih stabil dengan tingkat daya serap air yang tinggi. Hidrogel tersebut memiliki potensi untuk digunakan sebagai penutup luka.
Keyword: selulosa, nanofiber selulosa, hidrogel, alkaline treatment

Judul: Isolasi Selulosa Nanokristal Menggunakan Metode Hidrolisis Asam dan Enzim.
Abstrak: Selulosa merupakan kandungan paling banyak dari tandan kosong kelapa sawit yaitu sebesar 35.66%-57.75%. Sedangkan pada selulosa hasil delignifikasi dari tandan kosong kelapa sawit memiliki kandungan selulosa sebesar 70.17%. Ketersediaan selulosa ini melatarbelakangi riset tentang isolasi selulosa nanokristal. Isolasi selulosa nanokristal dari tandan kosong kelapa sawit dilakukan dengan dua metode hidrolisis, yaitu hidrolisis asam dan hidrolisis enzim. Hidrolisis asam untuk mengisolasi selulosa nanokristal menggunakan asam sulfat konsentrasi 55% (v/v) dan hidrolisis dilakukan selama 6 jam pada suhu 35oC. Proses isolasi dilanjutkan dengan hidrolisis enzim. Enzim yang digunakan adalah enzim selulase complex. Perlakuan yang dijadikan parameter adalah waktu hidrolisis dan konsentrasi enzim. Tingkat waktu hidrolisis yang digunakan meliputi 12 jam, 24 jam, 36 jam, dan 48 jam Sedangkan konsentrasi enzim yang dilakukan pada riset adalah 10%, 15%, 20%, dan 25% (b/b). Berat selulosa nanokristal tidak dipengaruhi oleh waktu hidrolisis dan konsentrasi enzim, berat tertinggi 9.41 gram diperoleh pada waktu hidrolisis 12 jam dengan konsentrasi enzim 10%. Distribusi ukuran partikel dipengaruhi oleh waktu hidrolisis dan interaksi antara waktu hidrolisis dan konsentrasi enzim dengan hasil terbaik 521.3 nm diperoleh pada perlakuan waktu hidrolisis 12 jam dengan konsentrasi enzim 20%. Kristalinitas tertinggi diperoleh pada perlakuan waktu hidrolisis 36 jam yaitu 25.3%. Kestabilan dispersi terbaik diperoleh pada waktu hidrolisis 24 jam dengan konsentrasi enzim 15%. Kadar gula reduksi dan protein dipengaruhi oleh waktu hidrolisis, konsentrasi enzim dan interaksi antara waktu hidrolisis dan konsentrasi enzim.
Keyword: selulosa, hidrolisis enzim, selulosa nanokristal

Judul: Exchange Market Pressure and Central Bank Intervention for Three ASEAN Countries
Abstrak: Two of the exchange rate systems which are adopted by many countries are the floating and the fixed exchange rate system. Both the exchange rate systems have different characteristics. Countries that implement fixed exchange rates system tend to set their domestic currency exchange rate at a certain point. On the contrary, countries which implement floating exchange rate system tend to let their domestic currency exchange rate to move flexibly and thus their value will always change according to the demand and supply of the currency in the foreign exchange market. Countries which implement floating exchange rate system are facing the risk of fluctuation in the exchange rate of their domestic currency against foreign currencies. The currency exchange rate fluctuation may be caused by economic problems such as a financial crisis. A country can also be potentially affected by other countries’ earlier financial crisis. This effect could potentially happen if these countries are in the same region, such as ASEAN. The 1997 ASEAN economic crisis was an example of a country’s financial crisis could affect other countries. At that time, some countries such as Indonesia, Malaysia and Thailand had to change their currency exchange rate system from the fixed exchange rate system to the floating exchange rate system due to the high costs which has to be incurred if they were to enforce the fixed exchange rate system. During 2002 until 2012, the domestic exchange rate of Indonesia, Malaysia and Thailand against the U.S. dollar had tended to fluctuate. If the domestic currency exchange rate fluctuated excessively then the central bank would intervene to stabilize the exchange rate in the foreign exchange market. The pressure on domestic currency exchange rate pressures has forced the central bank to intervene. The amount of those pressures can be analyzed by calculating the Exchange Market Pressure (EMP) index. Apart from that, the time when interventions are done by the central bank can be known based on EMP by calculating the Exchange Market Intervention (EMI) index. The purposes of this study were to determine the level of international pressure on the currency exchange market and monetary authorities intervene in three ASEAN countries, as well as to determine the effect of the monetary authorities intervene on the exchange rate of the domestic currency against the U.S. dollar in those three ASEAN countries. Based on the EMP index calculation results which are obtained during 2002 to 2012 period, the exchange rate of Indonesia, Malaysia and Thailand’s domestic currency had always fluctuated and the results of the EMP index indicated that each country were under diverse level of currency exchange rate appreciation and depreciation pressures. Thailand was the country with the highest currency exchange rate pressure compared to Indonesia and Malaysia. The results on the intervention index calculation showed that Indonesia, Malaysia and Thailand have intervention index between zero and one and more than one. We can also see from the intervention index that Indonesia and Thailand implement the controlled floating currency exchange rate instead of the freely floating one. Based on the calculation of the currency exchange rate by comparing
Keyword: exchange rate, exchange market pressure, intervention