Judul: Pengaruh efektifitas herbisida diuron 500 g/l sc dalam pengendalian gulma pada tanaman tebu (Saccharum officinarum l)
Abstrak: The experiment was conducted to test the efficacy of Diuron 500 g/l SC berbicice of weeds in sugar cane cultivation is inferred based on statistical analysis of the target weed species biomass data. The experiment was conducted PT. PG.PG Rajawali II Unit.. Subang is located in block cidangdeur Pasirbungur village, District Purwadadi, Subang regency, West Java, in January 2011 to March 2011. Experimental design used in this study was a randomized complete randimized design (RKLT) with one factor. This study used six treatments with four rplications. The treatment given is : (P1) Diuron 500 g/I SC with a dose of 0.5 i/ha, (P2)Diuron 500 g/l SC with a dose of 1.0/ha, (P3 Diuron 500 g/l SC with a dose of 2.0 i/ha, (P4) Diuron 500 g/l SC at a dose of 3.0 i/ha, (P5) Manual Weeding, (P6) Control. Diuron 500 g/l SC herbicide effectively suppress weed growth by 10 MSA. In statistical calculations, the average herbicide treatment with a dose of 0.5l/ha, 1.0l/ha, 2.0 l/ha, and 3.0 l/ha showed no significant difference in controlling weed growth an dsignificantly different from control treatment. During the trial found no symptoms of poisoning at treatment doses of 0.5-2.0 l/ha, but on treatment with a dose of 3.0.1 /ha showed mild toxicity scoring or not too harmful
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Judul: Pengaruh herbisida diuron 78.5% WP terhadap pengendalian gulma pada pertanaman tebu (Saccharum officinarum L.)
Abstrak: Percobaan ini dilakukan untuk mengetahui pengaruh dan keefektifan herbisida Maron 80 WP ( Diuron 78.5 %) pada berbagai tingkat dosis dalam mengendalikan gulma pada pertanaman tebu. Penelitian ini dilakukan di PG Rajawali II Subang Jawa Barat pada bulan Desember 2010 sampai Maret 2011. Penelitian menggunakan rancangan acak kelompok dengan faktor tunggal dan terdiri dari empat ulangan. Perlakuan yang diberikan adalah : Herbisida Maron 80 WP dengan dosis 2.0 kg/ha, herbisida Maron 80 WP dengan dosis 1.5 kg/ha, Herbisida Maron 80 WP dengan dosis 1.0 kg/ha, Herbisida Maron 80 WP dengan dosis 0.5 kg/ha, pengendalian manual dan kontrol. Berdasarkan analisis vegetasi sebelum aplikasi herbisida didapatkan empat spesies gulma dominan yaitu Digitaria adscendes, Borreria alata, Cleome rutidosperma dan Brachiaria distachya. Spesies gulma lain sebelum aplikasi herbisida ini adalah Cynodon dactylon, Croton hirtus, Alocasia maccorhiza. Hasil analisis vegetasi akhir memberikan gambaran umum tentang dominasi gulma setelah aplikasi herbisida. Perlakuan herbisida Maron 80 WP (Diuron 78.5%) pada semua taraf dosis yang diberikan cukup efektif dalam mengendalikan gulma hingga 10 Minggu Setelah Aplikasi (MSA). Secara umum aplikasi herbisida Maron 80 WP (Diuron 78.5%) memberikan hasil yang berbeda nyata dengan perlakuan tanpa pengendalian (kontrol) dalam menekan bobot kering gulma total, gulma daun lebar dan gulma rumput. Perlakuan pengendalian manual kurang efektif dalam mengendalikan gulma dipertanaman tebu lahan kering. Hal ini dilihat dari biaya pengendalian yang cukup tinggi yaitu Rp. 350.000,00/ha dan bobot kering gulma yang masih tinggi. Selama percobaan tidak ditemukan gejala keracunan pada tanaman tebu yang sampai mematikan tanaman. Gejala keracunan ringan hanya terdapat pada sebagian kecil tanaman contoh yang diamati.
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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.
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