Judul: Pengaruh Bahan Organik Chitosan dan Pupuk Guano terhadap Pertumbuhan dan Perkembangan Anggrek Dendrobium ‘Woxinia’.
Abstrak: The purpose of this research was to study the effect of organic matter chitosan and fertilizer guano on the growth and development of the orchid Dendrobium 'Woxinia'. The experiment took place at the University Farm Green House, Cikabayan. The study lasted from February to August 2011. This study used a randomized design Completly Group with two factors with the first factor is the concentration of chitosan consisted of three levels of 0, 10 and 20 ppm/ plant. The second factor is the concentration of guano fertilizer with 3 levels of 0, 10 and 20 ml / l water. Observations performed every single week for 5 months. The result showed that treatment with 10 ppm chitosan gave is significantly increased the number of pseudobulb (1.4). Guano 10 ml/l increased plant height at 10-19 Weeks After Treatment (WAT) (23.64 cm average an 19 WAT). At 9 Weeks After Treatment (WAT), leaf length at 9 Weeks After Treatment.
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Judul: Pertumbuhan Anggrek Phalaenopsis amabilis pada Perlakuan Chitosan dan Asam Salisila
Abstrak: Phalaenopsis orchid plant vegetative growth is influenced by environmental condition such as light, temperature, and humidity. Certain organic material affected on the growth, development and plant resistance to pests and diseases, including chitosan and salicylic acid. The objective of this research was to test the application of organic compound chitosan and salicylic acid on the growth of Phalaenopsis amabilis. This research was arranged in a randomized completely design with organic compound as a single factor. There were six treatment, 3 ppm chitosan, chitosan 6 ppm, 5 ppm salicylic acid, salicylic acid 10 ppm and 3 ppm chitosan + 5 ppm salicylic acid. Each treatment was repeated five times with 3 plantlets per bottle. Organic compound were mixed in ½ MS in vitro medium and planlets were transfered to the treatment medium and cultured in the tissue culture laboratory for four weeks. Planlets subsequently were acclimatizated to spaghnum ii moss medium in greenhouse. Treatment were continued by spraying of organic compound to planlets every two weeks. The results of the experiment showed that the best treatment of organic compound, was chitosan 3 ppm. This is showed by length of youngest leaf and percentage growth of plant on treatment of chitosan 3 ppm.
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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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