Judul: Karakterisasi Morfologi dan Agronomi Jarak Pagar (Jatropha curcas L.) Beberapa Aksesi Indonesia Bagian Barat
Abstrak: Morfological and agronomical characterization are important in developing superior varieties of jatropha. In this study, characterization was aimed for analyzing qualitative and quantitative character of 15 accessions from 5 regions in western Indonesia, i.e. Medan, Bengkulu, Banten, Bogor, and Sukabumi. Based on 5 variables, i.e. number of branches, number of productive branches, number of fruits per plant,uniformity of fruits ripening, and time of flowering, there were 3 accessions that have best character. They were Banten I, Bengkulu I, and Sukabumi II. The qualitative characteristic identification showed that qualitative characterization was not influenced by accessions. Based on cluster analysis showed that at 80 % similarity level the 15 accessions could be classified into three main groups. Group I consist of Medan I, Bengkulu I, Bengkulu III, Bengkulu IV, Bogor I, Bogor II, Bogor III, Sukabumi I, Sukabumi II, Sukabumi III, and Sukabumi IV. Group II contain Banten I whereas Medan II, Bengkulu II, and Banten II could be grouped into Group III.
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Judul: Respon Morfologi dan Fisiologi Aksesi Jarak Pagar (Jatropha Curcas Linn) dalam Kondisi Cekaman Kekeringan di Pembibitan
Abstrak: Jatropha (Jatropha curcas Linn) is one of the popular raw material when it comes to biodiesel fuel producing. It is often to encounter the problem where the land that is available to plant these Jatropha is the one that is marginal, so that it is important to see the tolerance of these Jatropha accessions to drought. The experiment was conducted in one of the Green House in Cikabayan, Darmaga IPB while the chlorophyll test was conducted in Molecular Marker, Spectrophotometer, and UV-Vis laboratory that is owned by Agronomy and Horticulture Department, Faculty of Agricultural, Bogor Agricultural Institute. The Research was started in July 2011 and ended in March 2012. The experimental design that was used in this experiment is factorial randomized block design. The first factor that was observed is the tolerance to the drought that was done in three degree which was 30%, 55%, and 80% of soil water content in the experimental field capacity. The second factor that was observed were 10 Jathropa accessions which have been evaluated, they were IP-3M, Jatim 013, Jatim 045, NTT 065,NTT 080, NTB 019, NTB 047, NTB 116, Sulawesi 72 and Sulawesi 117. Based on the a and b chlorophyll test that have been conducted Jatim 045 accessions signify the best result of treatment (the highest tolerance to drought). While from the scoring test the highest tolerance to drought in between 35% and 80% soil water content is shown by the NTT 065 accessions and the highest tolerance to drought in between 55% and 80% soil water content is shown by the Jatim 045 and NTB 047 accessions. There is no interaction occurs to both of the factors that were tested.
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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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