Judul: Pertumbuhan tanaman jarak pagar (Jatropha curcas L.) pada lahan pasca tambang timah di Bangka yang diberi pupuk organik, anorganik, dan hayati
Abstrak: The experiment aimed to examine the physiology and adaptation of accessions of Jatropha curcas L. given organic material in post tin mining land; to examine physiological processes of physic nut fed organic matter and nutrient contained NPK, and to examine the role of the root endophytic fungi Aspergillus niger to physiology and accession adaptation of physic nut in post tin mining land. The main plots in experiment 1 were 7 accessions of physic nut i.e. Madiun, Ponorogo, Jember, Dompu, Lampung, Bengkulu, and Sukabumi. The subplots were control, compost, and cow dung. Experiment 2, the first factors were organic matter i.e. control and adding cow dung. The second factors were 0 g NPK, 50 g NPK, 90 g NPK, and 130 g NPK. Experiment 3, the first factors were seven accessions of physic nut similar to physic nut accessions in the first experiment. The second factors were control and adding endophytic fungi. The results showed that vegetative growth of seven accessions of physic nut not given organic material couldn’t reach the generative growth. Accession Dompu fed compost and accession Bengkulu fed cow manure showed the higher ability in generative growth of capsule number, seed number, and total grain yield per year. Physic nut growth in post tin mining land can be improved by providing nutrient NPK with 14% N, 14% P, and K 14% at 50 g dose of cow dung and adding as much as 4 kg per plant. Inoculation of endophytic fungi A. niger can enhance better vegetative growth for accessions of Sukabumi, Jember, and Dompu.
Keyword: 

Judul: Respon pertumbuhan dan produksi tanaman jarak pagar(Jatropha curcas Linn.) pada berbagai taraf pupuk N dan P
Abstrak: Penelitian ini dilakukan untuk mengetahui pengaruh pemupukan nitrogen dan fosfor serta interaksinya terhadap pertumbuhan dan produksi tanaman jarak pagar (Jatropha curcas Linn.). Penelitian dilaksanakan di Kebun Cikarawang, Darmaga, Bogor dari bulan Juli 2006 sampai bulan Maret 2007. Penelitian ini menggunakan rancangan faktorial dalam Rancangan Acak Kelompok (RAK). Perlakuan terdiri dari dua faktor yaitu tingkat pemupukan N dan tingkat pemupukan P. Pemupukan N terdiri dari 4 taraf yaitu 0 kg N/ha (NO), 67 kg N/ha (N1), 133 kg N/ha (N2), 267 kg N/ha (N3). Dosis pupuk P terdiri dari tiga taraf yaitu 0 kg P:Os/ha (PO), 100 kg P₂Os/ha (P1), 200 kg P₂Os/ha (P2). Setiap tanaman dipupuk K dengan dosis 200 kg KCV/ha. Tiap perlakuan diulang tiga kali sehingga terdapat 36 satuan percobaan. Penelitian ini dilakukan pada lahan seluas 864 m² yang dibagi menjadi 36 petak. Tiap petak berukuran 4 m x 6 m, dengan jarak tanam 2 m x 2 m dan tiap petak terdiri dari 6 tanaman, sisanya untuk jalan dan jarak antar petakan. Karena penelitian ini merupakan penelitian lanjutan, maka tanaman jarak pagar yang diamati telah ditanam oleh peneliti sebelumnya dan telah berumur 20 MST. Pemupukan dilakukan pada saat awal musim hujan yaitu sekitar 40 MST. Kegiatan-kegiatan dalam pemeliharaan tanaman meliputi penyiangan dan pengendalian hama dan penyakit tasaman Hasil penelitian menunjukkan bahwa perlakuan pupuk nitrogen meningkatkan semua parameter vegetatif (tinggi, jumlah daun, jumlah cabang, dan diameter batang) maupun generatif (hasil panen) hingga akhir pengamatan (54 MST). Perlakuan 67 kg N/ha sudah mampu meningkatkan semua karakter vegetatif dan generatif yang diamati Pupuk fosfor berpengaruh nyata terhadap semua parameter vegetatif (tinggi, jumlah daun, jumlah cabang, diameter, dan ILD) serta parameter generatif (hasil panen). Perlakuan 100 kg P₂O/ha sudah mampu meningkatkan pertumbuhan dan produksi tanaman jarak pagar. Interaksi antara pupuk nitrogen dan fosfor tidak memberikan pengaruh yang nyata terhadap pertumbuhan dan produksi tanaman jarak pagar hingga akhir pengamatan (54 MST).
Keyword: 

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
Keyword: