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: Kinerja Antikorosi Zink Diarilditiofosfat dengan Teknik Polarisasi Potensiodinamika
Abstrak: Zinc diaryldithiophosphate (ZDTP) is a lubricant additive that functions as antiwear, anticorrosion, antioxidant, and antifriction. The ZDTP function has been studied in this experiment by measuring its function as anticorrosion using potentiodynamic polarization technique. The highest ZDTP yield was 70%. The measurement shows that ZDTP has high corrosion inhibiton effectivity as proved by the optimum value of %IE in the concentration 1% of inhibitor solution of 84.45% with surface coverage of 0.84. Thermodynamic parameter shows corrosion spontaneity decreased due to the present of inhibitor. The value of activation energy in Cu metal corrosion process with the present of inhibitor was 52.32 kJ mol-1, the value is higher than the blank activation energy, i.e 31.47 kJ mol-1. This fact shows a decreasing corrosion rate with increasing minimum energy of reaction.
Keyword: Bogor Agricultural University (IPB), zinc diaryldithiophosphate, thermodynamics, inhibition effectiveness, activation energy

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