Judul: Formulasi Surfaktan Metil Ester Sulfonat (MES) untuk Acid Stimulation Agent pada Lapangan Sandstone (Studi Kasus: Lapangan B)
Abstrak: Reservoir productivity normally declines with producing time or may be low initially. Acid stimulation is a method to increase the productivity of oil and gas wells. For sandstone field, hidrofluoride acid (HF) and some additives are ussually used as the solution for an acid stimulation agent. Methyl ester sulfonate (MES) can be used as one of the additives. MES for acid stimulation methods have a role to reduce the interfacial tension and modify wettability of the reservoir rock oil-wet to water-wet. The objective of this research is to obtain a formula with the best concentrations of MES or SMES that can reduce interfacial tension and combined with HF at various concentrations to enlarge rock pores. The best formula will be employed for futher testing in the laboratory. The performance tests included were thermal stability test, phase behavior and wettability. The best formula found for acid stimulation agent is surfactant MES 3% with addition of HF 9%. The results of performance test indicated that the thermal stability test at 80 0C can dissolves rocks up to 77.48% and have increased contact angle. For wettability test, the result obtained of the five treatments are that the contact angel increase significantly although more than 90 º. While the results of the phase behavior test was known that phase formed was in top phase or type II (+).
Keyword: methyl ester sulfonate, Acid stimulation agent

Judul: Formulasi Surfaktan MES Sebagai Acid Stimulation Agent untuk Lapangan Karbonat (Studi Kasus: Lapangan T)
Abstrak: The decrease of oil well productivity can be affected by the scale blockage and the conditions inside of the oil well. This problem can be solved by stimulating the oil well with an acid stimulation agent. This chemical solution contains of surfactant, brine, and acid. The surfactant reduces the interfacial and surface tension, the brine dissolves the surfactant, and the acid has a function as carbonate scale solvent. This research was conducted to find the formula of acid stimulation agent that gives the best performance to improve the oil well productivity. The materials used in this research were the oil well fluids that consist of formation water and crude oil from T oil field. The surfactants (MES and SMES) concentration used in this research was 0.5%, 1%, 1.5%, 2%; 3%, 4%, 5%, and 6% (w/w). HCl concentration added to surfactant solution were 5%, 10%, and 15% (w/w). At the last, 2% CH3COOH was added to this formula. The formula that gave the best performance was SMES 4% + HCl 5% + CH3COOH 2% with IFT value 6.74x10-2 dyne/cm and the solubility degree 20.7%. This formula has good resistance to high temperature of 90oC and has good capability of changing the core wettability to become more water-wet.
Keyword: acid stimulation agent, acid, methyl ester sulphonate, carbonate scale

Judul: Biologi parasitoid telur Trichogramma sp. (Hym. : Trichogrammatidae) dan Telenomus sp. (Hym. : Scelionidae) pada penggerek padi kuning Scirpophaga incertulas (Walker) (Lep. : pyralidae)
Abstrak: Penggerek padi kuning merupakan salah satu hana utama tanaman padi. Ada tiga jenis parasitoid telur penggerek padi kuning di Indonesia yaitu: Trichogramma japonicum Ashm. (Hymenoptera: Trichogrammatidae), Telenomus rowani (Gahan) (Hymenoptera Scelionidae) dan Tetrastichus schoenobii Ferr. parasitoid telur Trichogramma sp. dan Telenomus sp. sangat penting untuk adalah diketahui. Aspek biologi yang diteliti : preferensi parasitoid pada berbagai umur telur penggerek padi kuning; siklus hidup parasitoid; kemampuan bertelur parasitoid pada telur yang sesuai; preferensi parasitoid pada berbagai kelompok telur,. serta superparasitisme dan parasitisme ganda. Juga dilakukan pengamatan lapangan untuk mengetahui komposisi parasitoid telur penggerek padi kuning di lapangan. ..dst
Keyword: Trichogramma, Telenomus, Hymenoptera