Judul: Pengoptimuman waktu penyalutan membran PVC dalam pembuatan elektrode selektif ion nitrat
Abstrak: Highly concentration of nitrate in environment especially in water can cause health issue. Therefore, nitrate level should be monitored periodically. The presence of nitrate in the water could be detected by ion-selective electrode (ISE) made of coated a wire electrode using polymeric membrane. The objectives of this research are to determine the optimum time of membrane coating and analytical performance of the ISE. The membranes used in this study were composed of, 35% PVC, 61% plasticizer, and 4% aliquot of 336-nitrate with various coating time of 10, 15, 20, 25, and 30 seconds. Based on the results, the optimum time of membrane coating was 20 seconds. ISE III showed the best Nernst factor of 59.70 mV/decade. The best Nernstian response was in concentration range of 10-4–10-1 M. The response time of the developed nitrate ISE was less than 1 minute. The detection limit was found to be 6.14  10-5 M. The developed nitrate ISE did not show interference by NO2 - ion, but encountered interference by the presence of CH3COO-, ClO4 -, H2PO4 -, and SO4 2- ions
Keyword: Bogor Agricultural University (IPB), PVC membrane, nitrate, ion selective electrode

Judul: Pembuatan dan pencirian elektrode selektif ion Lu3+ (Lutetium) dengan Ionofor 4- odekanadioilbis-(1-fenil-3-metil-5-pirazolon)
Abstrak: The ion selective electrode (ISE) performance is affected by the type of ionophore used. This research developed an Lu3+ ISE with dodecanedioylbis-(1- phenyl-3-methyl-5-pirazolone) (H2DdBP) as ionophore which has been proved selective in Lu3+ liquid-liquid extraction. The best composition of ISE obtained from this research was 33% PVC, 57% acetophenone, 5% H2DdBP, and 5% oleic acid. Linear measurement was obtained with Nernst factor of 16.57 mV/decade at 10-3−10-7 M concentration range in very acidic situation and response time was 15 to 250 seconds. ISE still could be used at pH 4 and 7, with 5% Nernst factor decrease after 30 days usage. Other ions such as Cu2+, Cd2+, Pb2+, Ni2+, Ca2+, and La3+ did not affect the measurement of ISE.
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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