Judul: Ketersediaan Besi   (Fe)   dan Mangan   dalam  Humic  Dystrudept  dan  Serapannya   Akibat   Pemberian   Beberapa   Bahan   Organik   pada   Budidaya  Tumpangsari   Tanaman   Brokoli   (Brassica   oleraceae)  dan   Petsai   (Brassica  pekinensis)
Abstrak: As alternative way to solve pollution problem that are happened because of modern farming practices is organic farming. The use of organic fertilizers have some real superiority than that of chemical one. Organic fertilizer contains some macro nutirients (N, P, K, Ca, Mg, etc) and micro nutrients (Fe, Mn, Cu, Zn, etc). Besides macro nutrients, these micro nutrients have own role which is needed by crop. Iron (Fe) and manganese (Mn) are two nutrients needed for the growth of a plant. This research was carried out to discover the effect of chickenmanure compost and goat manure compost as well as its combination with pesticides and Thitonia compost on the avaibility of Fe and Mn in soil, their absorption and the production of broccoli and petsai. This research was designed into Group Randomized Design with 6 treatments and 3 replications. Organic fertilizers, those were chicken manure compost (25 ton/ha), goat manure compost (25 ton/ha) and Thitonia compost (3 ton/ha) was applied a the treatments. The results of this research showed that the treatment of organic fertilizers (chicken manure and goat manure as well as its combination) gave significance effect to increase the growth of broccoli but did not increase the growth of petsay, the availability of Fe and Mn in soil and the production of broccoli and petsay. However, there was a tendency that the treatment of chicken manure compost and its combination was higher compared to that of goat manure compost and its combination on all parameter observed.
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Judul: Respon pertumbuhan dan serapan dan hara Cu, Fe, Mn dan Zn pada tanaman kangkung dan bayam dengan pemberian pupuk organik dan anorganik
Abstrak: Mineral nutrients generally categorized as macronutrients and micronutrients. Nutrients Cu, Fe, Mn and Zn were essential for plant because these nutrients have an important role in plant metabolism. The aim of the research was to know the growth response and absorption of micro nutrients Cu, Fe, Mn and Zn of Kangkong and Spinach with organic (cow dung and worm cast) and inorganic fertilizers application (Urea, SP-36, KCI). P1 treatment was the mixed of soil and inorganic fertilizer (Urea 200 kg/ha, SP-36 100 kg/ha, KCI 100 kg/ha for the Kangkong; Urea 200 kg/ha, SP-36 195 kg/ha, and KCI 120 kg/ha for the Spinach). P2 treatment was the mixed of soil and cow dung (30 ton/ha for kangkong and 10 ton/ha for spinach); P3 treatment was the mixed of soil and worm cast of Eisenia foetida (30 ton/ha for kangkong and 10 ton/ha for spinach) and P4 as control. The result showed the given organic and inorganic fertilizers did not affect to all vegetative growth that observed. Nevertheless, plant with organic fertilizer application showed higher average values to all vegetative parameters that observed compared to inorganic fertilizer or control plants. Plant with organic fertilizer treatment also showed higher absorption of macronutrients and micronutrients compared to inorganic and control treatment. Kangkong plants with cow dung treatment showed absorption of micronutrients Fe, Mn, Zn and Cu respectively 511.8 ppm, 123.1 ppm, 93.2 ppm, and 13.4 ppm. Spinach plants with cow dung treatment showed absorption of Fe, Mn, Zn and Cu respectively 354.4 ppm, 104.7 ppm, 102.7 ppm and 12.8 ppm. Control plant showed low average values to all vegetative parameters that observed.
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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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