Judul: Karakterisasi Membran Komposit Nilon-Arang Untuk Proses Filtrasi Timbal.
Abstrak: Research about membrane technology that made from nylon thread with extra banana peel kepok charcoal had been done. Membranes had been made from ingredient variation, there are 6.9 g, 6.6 g, 6.5 g, 6.5 g, and 6.5 g nilon thread which added by ingredient of banana peel kepok charcoal in a series are 0.1 g, 0.4 g, 0.5 g, 0.75 g, and 0.25 g. This research had been analyzed about electrical properties, mechanic, and FTIR (Fourier Transform Infra Red) spectrum from membranes that had been made. In addition, the resulting solution filtration tested include density, viscosity, and metal content. Result of this research showed that membrane with ingredient 6.5 g nylon thread added 0.5 g banana peel kepok charcoal is good enough to degradate plumbum in the water. Electrical properties tested by LCR meter showed that the shift curves that prove a change in the electrical properties of the membrane before and after filtration. FTIR tested showed that banana peel charcoal has functional group that are stretching O-H, C=N, C=C, C-N aromatic and C-O. Membrane of nilon thread which added banana peel kepok charcoal has functional group amide and hydrocarbon but both of them are overlap.
Keyword: Bogor Agricultural University (IPB), plumbum, membrane, filtration, Banana peel kepok charcoal

Judul: Kajian Membran Nilon pada Proses Filtrasi Bertahap Sistem Cross-Flow untuk Desalinasi Air Payau
Abstrak: The membrane is semi-permeable coating that can form a thin layer separating the two phases with different characters. The membrane used was a nylon membrane. Membrane is used as a filter for the filtration process gradual cross-flow system. Cross-flow technique used to filter the water by passing the water on the membrane with 90° angular position to the normal line of membrane with the variation of the mass 6, 6.5 and 7 g. The filtration was done at pressure of 2.5, 5, 6, 7 and 8 psi. Each membrane was tested for compressive strength and tensile strength before and after each used. SEM test used to see the surface morphology of membrane before and after each used. In brackish water was done flux test and rejection test such as turbidity, salinity, density, and ph. Tests were performed on each filtration flux where the highest flux value is at 6 g membrane. The best rejection and mechanical test at 6.5 g membrane.
Keyword: Bogor Agricultural University (IPB), flux, cross-flow, filtration, nylon, membrane

Judul: Pengaruh vaksinasi terhadap dinamika populasi pada model SIR (Susceptible-Infected-Recovered)
Abstrak: SIR model can be used to model the spread of diseases in a closed population based on certain assumptions. In this research, the SIR model is formulated by including the factor of vaccination. As the result, the model has been shown to have two equilibrium points, i.e. disease free and endemic equilibrium. A simulation study is carried out to illustrate the model. The results show that some equilibrium points are asymptotically stable. Moreover, a minimum level of vaccination has been defined. For the vaccination level less than the minimum level, increase in the vaccination level results in decrease of the proportion of infected individuals in the corresponding equilibrium point. On the other hand, for the vaccination level greater than the minimum level, increase in the vaccination level results in decrease the proportion of susceptible individuals in the corresponding equilibrium point. Furthermore, when vaccination level is greater than the minimum level, it is found that the time needed for the disease to extinct is shorter.
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