Judul: Sintesis Zink Diisoamilditiofosfat pada Medium Kloroform dan Karakterisasi Kinerja Inhibisinya terhadap Korosi Logam Tembaga yang Diukur secara Polarisasi Potensiodinamik
Abstrak: Zinc dialkyldithiophosphate (ZDTP) is a complex compound known as a lubricant additive that has many functions such as anticorrosive, antifriction, and antioxidants. Zinc diisoamyldithiophosphate (ZDTPi) was synthesized using isoamyl alcohol in chloroform medium and was characterized for its anticorrosive performance using potentiodynamic polarization method. The measurement at concentration of 0.5, 1, 2, and 3% (w/v) indicated that the effectiveness of the inhibition of Cu metal corrosion increased in line with the addition of ZDTPi concentration. The thermodynamic parameters verification indicated that the ΔG* value increased from blank to sample; showing that the spontaneity of corrosion decreased in the presence of corrosion inhibitors. The activation energy of the sample was higher than the blank. Based on the increase of the minimum reaction energy, this phenomenon indicates the decreasing corrosion rate.
Keyword: Bogor Agricultural University (IPB), zinc dialkyldithiophosphate, polarization, corrosion inhibitor, inhibition affectivity

Judul: Sintesis Zink Diisoamilditiofosfat pada Medium Heptana dan Karakterisasi Kinerja Inhibisinya terhadap Korosi Logam Tembaga yang Diukur secara Polarisasi Potensiodinamik
Abstrak: Zinc dialkyldithiophosphates (ZDTP) compound is known as a lubricant additive and has many functions, one of which is as anti-corrosion. ZDTPi was synthesized in 2 steps. The first step was formation of intermediates so called dialkyldithiophosphates acid (ADTP) as resulted from the reaction between diphosphorus pentasulfide (P2S5) and isoamyl alcohol. The second step was addition of metal oxide, ZnO. ZDTPi performance as an anti-corrosion was measured by potentiodynamic polarization technique. The inhibiton effectiveness of ZDTPi to metal Cu reached 98.77% in the 3% concentration of inhibitor solution. Thermodynamic parameter showed a decreasing spontaneity reaction in the presence of inhibitor. The activation energy increased due to the increasing inhibitor addition as indicated by the increasing minimum energy of reaction.
Keyword: Bogor Agricultural University (IPB), zink dialkyldithiophosphates, thermodynamic, potentiodynamic polarization, dialkyldithiophosphates acid, anti-corrosion

Judul: Karakteristik Anatomi Skelet Kepala Buaya senyulong (Tomistoma schlegelii).
Abstrak: Buaya sepit atau senyulong (Tomistoma schlegelii) merupakan jenis buaya asli Indonesia yang berhabitat di sungai-sungai Sumatera, Kalimantan, dan juga pedalaman Sulawesi. Salah satu ciri khas buaya senyulong adalah bentuk moncong yang runcing dan sempit, namun hingga saat ini informasi mengenai struktur skelet kepala buaya senyulong sangat terbatas. Penelitian ini bertujuan untuk mempelajari karakteristik anatomi skelet kepala buaya senyulong yang dikatikan dengan fungsi dan perilakunya. Penelitian dilakukan secara eksploratif dengan melakukan pengamatan, pencatatan, dan pengambilan gambar dari skelet kepala buaya senyulong. Skelet kepala berukuran panjang 70 cm, lebar 29 cm, dan tingggi 17 cm dengan permukaan kasar pada os nasale, os frontale, os maxilla, os mandibula, os lacrimale, os jugale. Jumlah gigi pada buaya ini sebanyak 78 buah, terdiri dari 4 buah gigi premaxila, 16 buah gigi maxila, dan 19 buah gigi mandibula. Pada regio orbitalis ditemukan dua pasang fenestrae temporales yang berkembang baik. Fenestra supratemporale merupakan lubang oval yang membentang di sepanjang os parietale. Fenestra infratemporale berbentuk segitiga dan dibatasi oleh os squamosum, os postorbitale, os jugulare, dan os quadratum. Os mandibula hewan ini mempunyai symphysis mandibularis yang panjang yaitu garis yang melintang di corpus mandibulae. Secara fungsional ukuran symphysis mandibularis berkaitan dengan adaptasi hewan terhadap diet makan.
Keyword: kepala, moncong, Tomistoma schlegelii